import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Iterator;
import java.io.BufferedWriter;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.util.NoSuchElementException;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Egor Kulikov (egor@egork.net)
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        TaskA solver = new TaskA();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskA {
        public void solve(int testNumber, InputReader in, OutputWriter out) {
            int n = in.readInt();
            int m = in.readInt();
            int[] b = in.readIntArray(n);
            int[] g = in.readIntArray(m);
            ArrayUtils.sort(b);
            ArrayUtils.sort(g);
            if (b[n - 1] > g[0]) {
                out.printLine(-1);
                return;
            }
            long answer = 0;
            for (int i = 0; i < n - 1; i++) {
                answer += (long) b[i] * m;
            }
            answer += ArrayUtils.sumArray(g);
            if (b[n - 1] != g[0]) {
                answer += b[n - 1] - b[n - 2];
            }
            out.printLine(answer);
        }

    }

    static abstract class IntAbstractStream implements IntStream {
        public String toString() {
            StringBuilder builder = new StringBuilder();
            boolean first = true;
            for (IntIterator it = intIterator(); it.isValid(); it.advance()) {
                if (first) {
                    first = false;
                } else {
                    builder.append(' ');
                }
                builder.append(it.value());
            }
            return builder.toString();
        }

        public boolean equals(Object o) {
            if (!(o instanceof IntStream)) {
                return false;
            }
            IntStream c = (IntStream) o;
            IntIterator it = intIterator();
            IntIterator jt = c.intIterator();
            while (it.isValid() && jt.isValid()) {
                if (it.value() != jt.value()) {
                    return false;
                }
                it.advance();
                jt.advance();
            }
            return !it.isValid() && !jt.isValid();
        }

        public int hashCode() {
            int result = 0;
            for (IntIterator it = intIterator(); it.isValid(); it.advance()) {
                result *= 31;
                result += it.value();
            }
            return result;
        }

    }

    static class ArrayUtils {
        public static long sumArray(int[] array) {
            return new IntArray(array).sum();
        }

        public static int[] sort(int[] array) {
            return sort(array, IntComparator.DEFAULT);
        }

        public static int[] sort(int[] array, IntComparator comparator) {
            return sort(array, 0, array.length, comparator);
        }

        public static int[] sort(int[] array, int from, int to, IntComparator comparator) {
            if (from == 0 && to == array.length) {
                new IntArray(array).sort(comparator);
            } else {
                new IntArray(array).subList(from, to).sort(comparator);
            }
            return array;
        }

    }

    static interface IntList extends IntReversableCollection {
        public abstract int get(int index);

        public abstract void set(int index, int value);

        public abstract void addAt(int index, int value);

        public abstract void removeAt(int index);

        default public void swap(int first, int second) {
            if (first == second) {
                return;
            }
            int temp = get(first);
            set(first, get(second));
            set(second, temp);
        }

        default public IntIterator intIterator() {
            return new IntIterator() {
                private int at;
                private boolean removed;

                public int value() {
                    if (removed) {
                        throw new IllegalStateException();
                    }
                    return get(at);
                }

                public boolean advance() {
                    at++;
                    removed = false;
                    return isValid();
                }

                public boolean isValid() {
                    return !removed && at < size();
                }

                public void remove() {
                    removeAt(at);
                    at--;
                    removed = true;
                }
            };
        }

        default public void add(int value) {
            addAt(size(), value);
        }

        default public IntList sort(IntComparator comparator) {
            Sorter.sort(this, comparator);
            return this;
        }

        default public IntList subList(final int from, final int to) {
            return new IntList() {
                private final int shift;
                private final int size;

                {
                    if (from < 0 || from > to || to > IntList.this.size()) {
                        throw new IndexOutOfBoundsException("from = " + from + ", to = " + to + ", size = " + size());
                    }
                    shift = from;
                    size = to - from;
                }

                public int size() {
                    return size;
                }

                public int get(int at) {
                    if (at < 0 || at >= size) {
                        throw new IndexOutOfBoundsException("at = " + at + ", size = " + size());
                    }
                    return IntList.this.get(at + shift);
                }

                public void addAt(int index, int value) {
                    throw new UnsupportedOperationException();
                }

                public void removeAt(int index) {
                    throw new UnsupportedOperationException();
                }

                public void set(int at, int value) {
                    if (at < 0 || at >= size) {
                        throw new IndexOutOfBoundsException("at = " + at + ", size = " + size());
                    }
                    IntList.this.set(at + shift, value);
                }

                public IntList compute() {
                    return new IntArrayList(this);
                }
            };
        }

    }

    static interface IntComparator {
        public static final IntComparator DEFAULT = (first, second) -> {
            if (first < second) {
                return -1;
            }
            if (first > second) {
                return 1;
            }
            return 0;
        };

        public int compare(int first, int second);

    }

    static class Sorter {
        private static final int INSERTION_THRESHOLD = 16;

        private Sorter() {
        }

        public static void sort(IntList list, IntComparator comparator) {
            quickSort(list, 0, list.size() - 1, (Integer.bitCount(Integer.highestOneBit(list.size()) - 1) * 5) >> 1,
                    comparator);
        }

        private static void quickSort(IntList list, int from, int to, int remaining, IntComparator comparator) {
            if (to - from < INSERTION_THRESHOLD) {
                insertionSort(list, from, to, comparator);
                return;
            }
            if (remaining == 0) {
                heapSort(list, from, to, comparator);
                return;
            }
            remaining--;
            int pivotIndex = (from + to) >> 1;
            int pivot = list.get(pivotIndex);
            list.swap(pivotIndex, to);
            int storeIndex = from;
            int equalIndex = to;
            for (int i = from; i < equalIndex; i++) {
                int value = comparator.compare(list.get(i), pivot);
                if (value < 0) {
                    list.swap(storeIndex++, i);
                } else if (value == 0) {
                    list.swap(--equalIndex, i--);
                }
            }
            quickSort(list, from, storeIndex - 1, remaining, comparator);
            for (int i = equalIndex; i <= to; i++) {
                list.swap(storeIndex++, i);
            }
            quickSort(list, storeIndex, to, remaining, comparator);
        }

        private static void heapSort(IntList list, int from, int to, IntComparator comparator) {
            for (int i = (to + from - 1) >> 1; i >= from; i--) {
                siftDown(list, i, to, comparator, from);
            }
            for (int i = to; i > from; i--) {
                list.swap(from, i);
                siftDown(list, from, i - 1, comparator, from);
            }
        }

        private static void siftDown(IntList list, int start, int end, IntComparator comparator, int delta) {
            int value = list.get(start);
            while (true) {
                int child = ((start - delta) << 1) + 1 + delta;
                if (child > end) {
                    return;
                }
                int childValue = list.get(child);
                if (child + 1 <= end) {
                    int otherValue = list.get(child + 1);
                    if (comparator.compare(otherValue, childValue) > 0) {
                        child++;
                        childValue = otherValue;
                    }
                }
                if (comparator.compare(value, childValue) >= 0) {
                    return;
                }
                list.swap(start, child);
                start = child;
            }
        }

        private static void insertionSort(IntList list, int from, int to, IntComparator comparator) {
            for (int i = from + 1; i <= to; i++) {
                int value = list.get(i);
                for (int j = i - 1; j >= from; j--) {
                    if (comparator.compare(list.get(j), value) <= 0) {
                        break;
                    }
                    list.swap(j, j + 1);
                }
            }
        }

    }

    static class IntArray extends IntAbstractStream implements IntList {
        private int[] data;

        public IntArray(int[] arr) {
            data = arr;
        }

        public int size() {
            return data.length;
        }

        public int get(int at) {
            return data[at];
        }

        public void addAt(int index, int value) {
            throw new UnsupportedOperationException();
        }

        public void removeAt(int index) {
            throw new UnsupportedOperationException();
        }

        public void set(int index, int value) {
            data[index] = value;
        }

    }

    static class OutputWriter {
        private final PrintWriter writer;

        public OutputWriter(OutputStream outputStream) {
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
        }

        public OutputWriter(Writer writer) {
            this.writer = new PrintWriter(writer);
        }

        public void close() {
            writer.close();
        }

        public void printLine(long i) {
            writer.println(i);
        }

        public void printLine(int i) {
            writer.println(i);
        }

    }

    static interface IntIterator {
        public int value() throws NoSuchElementException;

        public boolean advance();

        public boolean isValid();

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private InputReader.SpaceCharFilter filter;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int[] readIntArray(int size) {
            int[] array = new int[size];
            for (int i = 0; i < size; i++) {
                array[i] = readInt();
            }
            return array;
        }

        public int read() {
            if (numChars == -1) {
                throw new InputMismatchException();
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }

        public int readInt() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public boolean isSpaceChar(int c) {
            if (filter != null) {
                return filter.isSpaceChar(c);
            }
            return isWhitespace(c);
        }

        public static boolean isWhitespace(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);

        }

    }

    static interface IntCollection extends IntStream {
        public int size();

        default public void add(int value) {
            throw new UnsupportedOperationException();
        }

        default public IntCollection addAll(IntStream values) {
            for (IntIterator it = values.intIterator(); it.isValid(); it.advance()) {
                add(it.value());
            }
            return this;
        }

    }

    static class IntArrayList extends IntAbstractStream implements IntList {
        private int size;
        private int[] data;

        public IntArrayList() {
            this(3);
        }

        public IntArrayList(int capacity) {
            data = new int[capacity];
        }

        public IntArrayList(IntCollection c) {
            this(c.size());
            addAll(c);
        }

        public IntArrayList(IntStream c) {
            this();
            if (c instanceof IntCollection) {
                ensureCapacity(((IntCollection) c).size());
            }
            addAll(c);
        }

        public IntArrayList(IntArrayList c) {
            size = c.size();
            data = c.data.clone();
        }

        public IntArrayList(int[] arr) {
            size = arr.length;
            data = arr.clone();
        }

        public int size() {
            return size;
        }

        public int get(int at) {
            if (at >= size) {
                throw new IndexOutOfBoundsException("at = " + at + ", size = " + size);
            }
            return data[at];
        }

        private void ensureCapacity(int capacity) {
            if (data.length >= capacity) {
                return;
            }
            capacity = Math.max(2 * data.length, capacity);
            data = Arrays.copyOf(data, capacity);
        }

        public void addAt(int index, int value) {
            ensureCapacity(size + 1);
            if (index > size || index < 0) {
                throw new IndexOutOfBoundsException("at = " + index + ", size = " + size);
            }
            if (index != size) {
                System.arraycopy(data, index, data, index + 1, size - index);
            }
            data[index] = value;
            size++;
        }

        public void removeAt(int index) {
            if (index >= size || index < 0) {
                throw new IndexOutOfBoundsException("at = " + index + ", size = " + size);
            }
            if (index != size - 1) {
                System.arraycopy(data, index + 1, data, index, size - index - 1);
            }
            size--;
        }

        public void set(int index, int value) {
            if (index >= size) {
                throw new IndexOutOfBoundsException("at = " + index + ", size = " + size);
            }
            data[index] = value;
        }

    }

    static interface IntStream extends Iterable<Integer>, Comparable<IntStream> {
        public IntIterator intIterator();

        default public Iterator<Integer> iterator() {
            return new Iterator<Integer>() {
                private IntIterator it = intIterator();

                public boolean hasNext() {
                    return it.isValid();
                }

                public Integer next() {
                    int result = it.value();
                    it.advance();
                    return result;
                }
            };
        }

        default public int compareTo(IntStream c) {
            IntIterator it = intIterator();
            IntIterator jt = c.intIterator();
            while (it.isValid() && jt.isValid()) {
                int i = it.value();
                int j = jt.value();
                if (i < j) {
                    return -1;
                } else if (i > j) {
                    return 1;
                }
                it.advance();
                jt.advance();
            }
            if (it.isValid()) {
                return 1;
            }
            if (jt.isValid()) {
                return -1;
            }
            return 0;
        }

        default public long sum() {
            long result = 0;
            for (IntIterator it = intIterator(); it.isValid(); it.advance()) {
                result += it.value();
            }
            return result;
        }

    }

    static interface IntReversableCollection extends IntCollection {
    }
}


import java.io.*;
import java.util.*;
import java.text.*;

public class a556{

	public static void main(String[] args) throws Exception
    {
	   //new FileInputStream("input.txt");
		//new FileOutputStream("output.txt")
		InputReader in = new InputReader(System.in);
		OutputWriter out = new OutputWriter(System.out);
		int n,m;
		n=in.ri();
		m=in.ri();
		int b[]=new int[n];
		int g[]=new int[m];
		for(int i=0;i<n;i++)b[i]=in.ri();
		for(int i=0;i<m;i++)g[i]=in.ri();
		Arrays.sort(b);
		Arrays.sort(g);
		long sum=0;
		if(g[0]<b[n-1])sum=-1;
		else if(g[0]==b[n-1]){
			for(int i=0;i<m;i++)sum+=g[i];
			for(int i=0;i<n-1;i++)sum+=(m*b[i]);
		}
		else{
			if(n==1)sum=-1;
			else {
				for(int i=0;i<m;i++)sum+=g[i];
				sum+=b[n-1];sum+=(b[n-2]*(m-1));
				for(int i=0;i<n-2;i++)sum+=(m*b[i]);

			}
		}

		out.pl(sum);
		out.close();
	}
private static class InputReader
	{
		private InputStream stream;
		private byte[] buf = new byte[1024];
		private int curChar;
		private int numChars;
		private SpaceCharFilter filter;

		public InputReader(InputStream stream)
		{
			this.stream = stream;
		}

		public int read()
		{
			if (numChars == -1)
				throw new InputMismatchException();
			if (curChar >= numChars)
			{
				curChar = 0;
				try
				{
					numChars = stream.read(buf);
				} catch (IOException e)
				{
					throw new InputMismatchException();
				}
				if (numChars <= 0)
				return -1;
			}
			return buf[curChar++];
		}

		public String rs()
        {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            StringBuilder res = new StringBuilder();
            do
            {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

		public int ri()
		{
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-')
			{
				sgn = -1;
				c = read();
			}
			int res = 0;
			do
			{
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}

		public double rd() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E')
                    return res * Math.pow(10, ri());
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E')
                        return res * Math.pow(10, ri());
                    if (c < '0' || c > '9')
                        throw new InputMismatchException();
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }

		public long rl() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

		public boolean isSpaceChar(int c)
		{
			if (filter != null)
				return filter.isSpaceChar(c);
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}

		public interface SpaceCharFilter
		{
			public boolean isSpaceChar(int ch);
		}
	}

	private static class OutputWriter
	{
		private final PrintWriter writer;

		public OutputWriter(OutputStream outputStream)
		{
			writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
		}

		public OutputWriter(Writer writer)
		{
			this.writer = new PrintWriter(writer);
		}
 		public void print(Object... objects)
		{
			for (int i = 0; i < objects.length; i++)
			{
				if (i != 0)
				writer.print(' ');
				writer.print(objects[i]);
			}
		}

		public void pf(double n)
		{
			writer.printf("%.9f%n", n);
		}
		public void pl(Object... objects)
		{
			print(objects);
			writer.println();
		}

		public void close()
		{
			writer.close();
		}

		public void flush()
		{
			writer.flush();
		}

	}
}


import java.io.*;
import java.util.*;
import java.text.*;

public class a556{

	public static void main(String[] args) throws Exception
    {
	   //new FileInputStream("input.txt");
		//new FileOutputStream("output.txt")
		InputReader in = new InputReader(System.in);
		OutputWriter out = new OutputWriter(System.out);
		int n,m;
		n=in.ri();
		m=in.ri();
		long b[]=new long[n];
		long g[]=new long[m];
		for(int i=0;i<n;i++)b[i]=in.rl();
		for(int i=0;i<m;i++)g[i]=in.rl();
		Arrays.sort(b);
		Arrays.sort(g);
		long sum=0;
		if(g[0]<b[n-1])sum=-1;
		else if(g[0]==b[n-1]){
			for(int i=0;i<m;i++)sum+=g[i];
			for(int i=0;i<n-1;i++)sum+=(m*b[i]);
		}
		else{
			if(n==1)sum=-1;
			else {
				for(int i=0;i<m;i++)sum+=g[i];
				sum+=b[n-1];sum+=(b[n-2]*(m-1));
				for(int i=0;i<n-2;i++)sum+=(m*b[i]);

			}
		}

		out.pl(sum);
		out.close();
	}
private static class InputReader
	{
		private InputStream stream;
		private byte[] buf = new byte[1024];
		private int curChar;
		private int numChars;
		private SpaceCharFilter filter;

		public InputReader(InputStream stream)
		{
			this.stream = stream;
		}

		public int read()
		{
			if (numChars == -1)
				throw new InputMismatchException();
			if (curChar >= numChars)
			{
				curChar = 0;
				try
				{
					numChars = stream.read(buf);
				} catch (IOException e)
				{
					throw new InputMismatchException();
				}
				if (numChars <= 0)
				return -1;
			}
			return buf[curChar++];
		}

		public String rs()
        {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            StringBuilder res = new StringBuilder();
            do
            {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

		public int ri()
		{
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-')
			{
				sgn = -1;
				c = read();
			}
			int res = 0;
			do
			{
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}

		public double rd() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E')
                    return res * Math.pow(10, ri());
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E')
                        return res * Math.pow(10, ri());
                    if (c < '0' || c > '9')
                        throw new InputMismatchException();
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }

		public long rl() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

		public boolean isSpaceChar(int c)
		{
			if (filter != null)
				return filter.isSpaceChar(c);
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}

		public interface SpaceCharFilter
		{
			public boolean isSpaceChar(int ch);
		}
	}

	private static class OutputWriter
	{
		private final PrintWriter writer;

		public OutputWriter(OutputStream outputStream)
		{
			writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
		}

		public OutputWriter(Writer writer)
		{
			this.writer = new PrintWriter(writer);
		}
 		public void print(Object... objects)
		{
			for (int i = 0; i < objects.length; i++)
			{
				if (i != 0)
				writer.print(' ');
				writer.print(objects[i]);
			}
		}

		public void pf(double n)
		{
			writer.printf("%.9f%n", n);
		}
		public void pl(Object... objects)
		{
			print(objects);
			writer.println();
		}

		public void close()
		{
			writer.close();
		}

		public void flush()
		{
			writer.flush();
		}

	}
}


import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.*;

public class CF1158 {
    public static void main(String[] args) throws Exception {
        boolean local = System.getProperty("ONLINE_JUDGE") == null;
        boolean async = false;

        Charset charset = Charset.forName("ascii");

        FastIO io = local ? new FastIO(new FileInputStream("D:\\DATABASE\\TESTCASE\\Code.in"), System.out, charset) : new FastIO(System.in, System.out, charset);
        Task task = new Task(io, new Debug(local));

        if (async) {
            Thread t = new Thread(null, task, "dalt", 1 << 27);
            t.setPriority(Thread.MAX_PRIORITY);
            t.start();
            t.join();
        } else {
            task.run();
        }

        if (local) {
            io.cache.append("\n\n--memory -- \n" + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) >> 20) + "M");
        }

        io.flush();
    }

    public static class Task implements Runnable {
        final FastIO io;
        final Debug debug;
        int inf = (int) 1e8;
        int mod = (int) 1e9 + 7;

        public int mod(int val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return val;
        }

        public int mod(long val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return (int) val;
        }

        int bitAt(int x, int i) {
            return (x >> i) & 1;
        }

        int bitAt(long x, int i) {
            return (int) ((x >> i) & 1);
        }

        public Task(FastIO io, Debug debug) {
            this.io = io;
            this.debug = debug;
        }

        @Override
        public void run() {
            solve();
        }

        public void solve() {
            int n = io.readInt();
            int m = io.readInt();
            int[] boys = new int[n];
            int[] girls = new int[m];

            long total = 0;
            for (int i = 0; i < n; i++) {
                boys[i] = io.readInt();
                total += (long) m * boys[i];
            }
            Arrays.sort(boys);
            int max = boys[n - 1];

            int minGirl = inf;
            for (int i = 0; i < m; i++) {
                girls[i] = io.readInt();
                minGirl = Math.min(minGirl, girls[i]);
                total += girls[i] - max;
            }

            if (minGirl < max) {
                io.cache.append(-1);
                return;
            }

            if (minGirl > max) {
                total += max - boys[n - 2];
            }

            io.cache.append(total);
        }
    }

    public static class FastIO {
        public final StringBuilder cache = new StringBuilder();
        private final InputStream is;
        private final OutputStream os;
        private final Charset charset;
        private StringBuilder defaultStringBuf = new StringBuilder(1 << 8);
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastIO(InputStream is, OutputStream os, Charset charset) {
            this.is = is;
            this.os = os;
            this.charset = charset;
        }

        public FastIO(InputStream is, OutputStream os) {
            this(is, os, Charset.forName("ascii"));
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public long readLong() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            long val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public double readDouble() {
            boolean sign = true;
            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+';
                next = read();
            }

            long val = 0;
            while (next >= '0' && next <= '9') {
                val = val * 10 + next - '0';
                next = read();
            }
            if (next != '.') {
                return sign ? val : -val;
            }
            next = read();
            long radix = 1;
            long point = 0;
            while (next >= '0' && next <= '9') {
                point = point * 10 + next - '0';
                radix = radix * 10;
                next = read();
            }
            double result = val + (double) point / radix;
            return sign ? result : -result;
        }

        public String readString(StringBuilder builder) {
            skipBlank();

            while (next > 32) {
                builder.append((char) next);
                next = read();
            }

            return builder.toString();
        }

        public String readString() {
            defaultStringBuf.setLength(0);
            return readString(defaultStringBuf);
        }

        public int readLine(char[] data, int offset) {
            int originalOffset = offset;
            while (next != -1 && next != '\n') {
                data[offset++] = (char) next;
                next = read();
            }
            return offset - originalOffset;
        }

        public int readString(char[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (char) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public int readString(byte[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (byte) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public char readChar() {
            skipBlank();
            char c = (char) next;
            next = read();
            return c;
        }

        public void flush() {
            try {
                os.write(cache.toString().getBytes(charset));
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        public boolean hasMore() {
            skipBlank();
            return next != -1;
        }
    }

    public static class Debug {
        private boolean allowDebug;

        public Debug(boolean allowDebug) {
            this.allowDebug = allowDebug;
        }

        public void assertTrue(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (!flag) {
                fail();
            }
        }

        public void fail() {
            throw new RuntimeException();
        }

        public void assertFalse(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (flag) {
                fail();
            }
        }

        private void outputName(String name) {
            System.out.print(name + " = ");
        }

        public void debug(String name, int x) {
            if (!allowDebug) {
                return;
            }

            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, long x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, double x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, int[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, long[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, double[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, Object x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, Object... x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.deepToString(x));
        }
    }

    public static class Randomized {
        static Random random = new Random(12345678);

        public static double nextDouble(double min, double max) {
            return random.nextDouble() * (max - min) + min;
        }

        public static void randomizedArray(int[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                int tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(long[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                long tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(double[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                double tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(float[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                float tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static <T> void randomizedArray(T[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                T tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static int nextInt(int l, int r) {
            return random.nextInt(r - l + 1) + l;
        }
    }

    public static class Mathematics {
        public static int ceilPowerOf2(int x) {
            return 32 - Integer.numberOfLeadingZeros(x - 1);
        }

        public static int floorPowerOf2(int x) {
            return 31 - Integer.numberOfLeadingZeros(x);
        }

        public static long modmul(long a, long b, long mod) {
            return b == 0 ? 0 : ((modmul(a, b >> 1, mod) << 1) % mod + a * (b & 1)) % mod;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static int gcd(int a, int b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static int gcd0(int a, int b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static int extgcd(int a, int b, int[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                int g = extgcd0(b, a, coe);
                int tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static int extgcd0(int a, int b, int[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            int g = extgcd0(b, a % b, coe);
            int n = coe[0];
            int m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static long gcd(long a, long b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static long gcd0(long a, long b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static long extgcd(long a, long b, long[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                long g = extgcd0(b, a, coe);
                long tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static long extgcd0(long a, long b, long[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            long g = extgcd0(b, a % b, coe);
            long n = coe[0];
            long m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get y where x * y = 1 (% mod)
         */
        public static int inverse(int x, int mod) {
            return pow(x, mod - 2, mod);
        }

        /**
         * Get x^n(% mod)
         */
        public static int pow(int x, int n, int mod) {
            int bit = 31 - Integer.numberOfLeadingZeros(n);
            long product = 1;
            for (; bit >= 0; bit--) {
                product = product * product % mod;
                if (((1 << bit) & n) != 0) {
                    product = product * x % mod;
                }
            }
            return (int) product;
        }

        public static long longpow(long x, long n, long mod) {
            if (n == 0) {
                return 1;
            }
            long prod = longpow(x, n >> 1, mod);
            prod = modmul(prod, prod, mod);
            if ((n & 1) == 1) {
                prod = modmul(prod, x, mod);
            }
            return prod;
        }

        /**
         * Get x % mod
         */
        public static int mod(int x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return x;
        }

        public static int mod(long x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return (int) x;
        }

        /**
         * Get n!/(n-m)!
         */
        public static long permute(int n, int m) {
            return m == 0 ? 1 : n * permute(n - 1, m - 1);
        }

        /**
         * Put all primes less or equal to limit into primes after offset
         */
        public static int eulerSieve(int limit, int[] primes, int offset) {
            boolean[] isComp = new boolean[limit + 1];
            int wpos = offset;
            for (int i = 2; i <= limit; i++) {
                if (!isComp[i]) {
                    primes[wpos++] = i;
                }
                for (int j = offset, until = limit / i; j < wpos && primes[j] <= until; j++) {
                    int pi = primes[j] * i;
                    isComp[pi] = true;
                    if (i % primes[j] == 0) {
                        break;
                    }
                }
            }
            return wpos - offset;
        }

        /**
         * Round x into integer
         */
        public static int intRound(double x) {
            if (x < 0) {
                return -(int) (-x + 0.5);
            }
            return (int) (x + 0.5);
        }

        /**
         * Round x into long
         */
        public static long longRound(double x) {
            if (x < 0) {
                return -(long) (-x + 0.5);
            }
            return (long) (x + 0.5);
        }
    }
}


import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.*;

public class CF1158 {
    public static void main(String[] args) throws Exception {
        boolean local = System.getProperty("ONLINE_JUDGE") == null;
        boolean async = false;

        Charset charset = Charset.forName("ascii");

        FastIO io = local ? new FastIO(new FileInputStream("D:\\DATABASE\\TESTCASE\\Code.in"), System.out, charset) : new FastIO(System.in, System.out, charset);
        Task task = new Task(io, new Debug(local));

        if (async) {
            Thread t = new Thread(null, task, "dalt", 1 << 27);
            t.setPriority(Thread.MAX_PRIORITY);
            t.start();
            t.join();
        } else {
            task.run();
        }

        if (local) {
            io.cache.append("\n\n--memory -- \n" + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) >> 20) + "M");
        }

        io.flush();
    }

    public static class Task implements Runnable {
        final FastIO io;
        final Debug debug;
        int inf = (int) 1e8;
        int mod = (int) 1e9 + 7;

        public int mod(int val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return val;
        }

        public int mod(long val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return (int) val;
        }

        int bitAt(int x, int i) {
            return (x >> i) & 1;
        }

        int bitAt(long x, int i) {
            return (int) ((x >> i) & 1);
        }

        public Task(FastIO io, Debug debug) {
            this.io = io;
            this.debug = debug;
        }

        @Override
        public void run() {
            solve();
        }

        public void solve() {
            int n = io.readInt();
            int m = io.readInt();
            int[] boys = new int[n];
            int[] girls = new int[m];

            int max = 0;
            TreeMap<Integer, Integer> set = new TreeMap<>();
            long total = 0;
            for (int i = 0; i < n; i++) {
                boys[i] = io.readInt();
                total += boys[i] * (long) m;
                set.put(boys[i], m - 1);
                max = Math.max(boys[i], max);
            }

            for (int i = 0; i < m; i++) {
                girls[i] = io.readInt();
                Integer min = set.floorKey(girls[i]);
                if (girls[i] < max || min == null) {
                    io.cache.append(-1);
                    return;
                }
                total += girls[i] - min;
                Integer count = set.get(min);
                if (count == 1) {
                    set.remove(min);
                } else {
                    set.put(min, count - 1);
                }
            }

            io.cache.append(total);
        }
    }

    public static class FastIO {
        public final StringBuilder cache = new StringBuilder();
        private final InputStream is;
        private final OutputStream os;
        private final Charset charset;
        private StringBuilder defaultStringBuf = new StringBuilder(1 << 8);
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastIO(InputStream is, OutputStream os, Charset charset) {
            this.is = is;
            this.os = os;
            this.charset = charset;
        }

        public FastIO(InputStream is, OutputStream os) {
            this(is, os, Charset.forName("ascii"));
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public long readLong() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            long val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public double readDouble() {
            boolean sign = true;
            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+';
                next = read();
            }

            long val = 0;
            while (next >= '0' && next <= '9') {
                val = val * 10 + next - '0';
                next = read();
            }
            if (next != '.') {
                return sign ? val : -val;
            }
            next = read();
            long radix = 1;
            long point = 0;
            while (next >= '0' && next <= '9') {
                point = point * 10 + next - '0';
                radix = radix * 10;
                next = read();
            }
            double result = val + (double) point / radix;
            return sign ? result : -result;
        }

        public String readString(StringBuilder builder) {
            skipBlank();

            while (next > 32) {
                builder.append((char) next);
                next = read();
            }

            return builder.toString();
        }

        public String readString() {
            defaultStringBuf.setLength(0);
            return readString(defaultStringBuf);
        }

        public int readLine(char[] data, int offset) {
            int originalOffset = offset;
            while (next != -1 && next != '\n') {
                data[offset++] = (char) next;
                next = read();
            }
            return offset - originalOffset;
        }

        public int readString(char[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (char) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public int readString(byte[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (byte) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public char readChar() {
            skipBlank();
            char c = (char) next;
            next = read();
            return c;
        }

        public void flush() {
            try {
                os.write(cache.toString().getBytes(charset));
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        public boolean hasMore() {
            skipBlank();
            return next != -1;
        }
    }

    public static class Debug {
        private boolean allowDebug;

        public Debug(boolean allowDebug) {
            this.allowDebug = allowDebug;
        }

        public void assertTrue(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (!flag) {
                fail();
            }
        }

        public void fail() {
            throw new RuntimeException();
        }

        public void assertFalse(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (flag) {
                fail();
            }
        }

        private void outputName(String name) {
            System.out.print(name + " = ");
        }

        public void debug(String name, int x) {
            if (!allowDebug) {
                return;
            }

            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, long x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, double x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, int[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, long[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, double[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, Object x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, Object... x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.deepToString(x));
        }
    }

    public static class Randomized {
        static Random random = new Random(12345678);

        public static double nextDouble(double min, double max) {
            return random.nextDouble() * (max - min) + min;
        }

        public static void randomizedArray(int[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                int tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(long[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                long tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(double[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                double tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(float[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                float tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static <T> void randomizedArray(T[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                T tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static int nextInt(int l, int r) {
            return random.nextInt(r - l + 1) + l;
        }
    }

    public static class Mathematics {
        public static int ceilPowerOf2(int x) {
            return 32 - Integer.numberOfLeadingZeros(x - 1);
        }

        public static int floorPowerOf2(int x) {
            return 31 - Integer.numberOfLeadingZeros(x);
        }

        public static long modmul(long a, long b, long mod) {
            return b == 0 ? 0 : ((modmul(a, b >> 1, mod) << 1) % mod + a * (b & 1)) % mod;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static int gcd(int a, int b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static int gcd0(int a, int b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static int extgcd(int a, int b, int[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                int g = extgcd0(b, a, coe);
                int tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static int extgcd0(int a, int b, int[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            int g = extgcd0(b, a % b, coe);
            int n = coe[0];
            int m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static long gcd(long a, long b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static long gcd0(long a, long b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static long extgcd(long a, long b, long[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                long g = extgcd0(b, a, coe);
                long tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static long extgcd0(long a, long b, long[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            long g = extgcd0(b, a % b, coe);
            long n = coe[0];
            long m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get y where x * y = 1 (% mod)
         */
        public static int inverse(int x, int mod) {
            return pow(x, mod - 2, mod);
        }

        /**
         * Get x^n(% mod)
         */
        public static int pow(int x, int n, int mod) {
            int bit = 31 - Integer.numberOfLeadingZeros(n);
            long product = 1;
            for (; bit >= 0; bit--) {
                product = product * product % mod;
                if (((1 << bit) & n) != 0) {
                    product = product * x % mod;
                }
            }
            return (int) product;
        }

        public static long longpow(long x, long n, long mod) {
            if (n == 0) {
                return 1;
            }
            long prod = longpow(x, n >> 1, mod);
            prod = modmul(prod, prod, mod);
            if ((n & 1) == 1) {
                prod = modmul(prod, x, mod);
            }
            return prod;
        }

        /**
         * Get x % mod
         */
        public static int mod(int x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return x;
        }

        public static int mod(long x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return (int) x;
        }

        /**
         * Get n!/(n-m)!
         */
        public static long permute(int n, int m) {
            return m == 0 ? 1 : n * permute(n - 1, m - 1);
        }

        /**
         * Put all primes less or equal to limit into primes after offset
         */
        public static int eulerSieve(int limit, int[] primes, int offset) {
            boolean[] isComp = new boolean[limit + 1];
            int wpos = offset;
            for (int i = 2; i <= limit; i++) {
                if (!isComp[i]) {
                    primes[wpos++] = i;
                }
                for (int j = offset, until = limit / i; j < wpos && primes[j] <= until; j++) {
                    int pi = primes[j] * i;
                    isComp[pi] = true;
                    if (i % primes[j] == 0) {
                        break;
                    }
                }
            }
            return wpos - offset;
        }

        /**
         * Round x into integer
         */
        public static int intRound(double x) {
            if (x < 0) {
                return -(int) (-x + 0.5);
            }
            return (int) (x + 0.5);
        }

        /**
         * Round x into long
         */
        public static long longRound(double x) {
            if (x < 0) {
                return -(long) (-x + 0.5);
            }
            return (long) (x + 0.5);
        }
    }
}


import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.*;

public class CF1158 {
    public static void main(String[] args) throws Exception {
        boolean local = System.getProperty("ONLINE_JUDGE") == null;
        boolean async = false;

        Charset charset = Charset.forName("ascii");

        FastIO io = local ? new FastIO(new FileInputStream("D:\\DATABASE\\TESTCASE\\Code.in"), System.out, charset) : new FastIO(System.in, System.out, charset);
        Task task = new Task(io, new Debug(local));

        if (async) {
            Thread t = new Thread(null, task, "dalt", 1 << 27);
            t.setPriority(Thread.MAX_PRIORITY);
            t.start();
            t.join();
        } else {
            task.run();
        }

        if (local) {
            io.cache.append("\n\n--memory -- \n" + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) >> 20) + "M");
        }

        io.flush();
    }

    public static class Task implements Runnable {
        final FastIO io;
        final Debug debug;
        int inf = (int) 1e8;
        int mod = (int) 1e9 + 7;

        public int mod(int val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return val;
        }

        public int mod(long val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return (int) val;
        }

        int bitAt(int x, int i) {
            return (x >> i) & 1;
        }

        int bitAt(long x, int i) {
            return (int) ((x >> i) & 1);
        }

        public Task(FastIO io, Debug debug) {
            this.io = io;
            this.debug = debug;
        }

        @Override
        public void run() {
            solve();
        }

        public void solve() {
            int n = io.readInt();
            int m = io.readInt();
            int[] boys = new int[n];
            int[] girls = new int[m];

            int max = 0;
            TreeMap<Integer, Integer> set = new TreeMap<>();
            Set<Integer> equalSet = new HashSet<>();
            long total = 0;
            for (int i = 0; i < n; i++) {
                boys[i] = io.readInt();
                total += boys[i] * (long) m;
                set.put(boys[i], m - 1);
                equalSet.add(boys[i]);
                max = Math.max(boys[i], max);
            }

            for (int i = 0; i < m; i++) {
                girls[i] = io.readInt();

                if (girls[i] < max) {
                    io.cache.append(-1);
                    return;
                }
                if (equalSet.contains(girls[i])) {
                    equalSet.remove(girls[i]);
                    continue;
                }
                Integer min = set.floorKey(girls[i]);
                total += girls[i] - min;
                Integer count = set.get(min);
                if (count == 1) {
                    set.remove(min);
                } else {
                    set.put(min, count - 1);
                }
            }

            io.cache.append(total);
        }
    }

    public static class FastIO {
        public final StringBuilder cache = new StringBuilder();
        private final InputStream is;
        private final OutputStream os;
        private final Charset charset;
        private StringBuilder defaultStringBuf = new StringBuilder(1 << 8);
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastIO(InputStream is, OutputStream os, Charset charset) {
            this.is = is;
            this.os = os;
            this.charset = charset;
        }

        public FastIO(InputStream is, OutputStream os) {
            this(is, os, Charset.forName("ascii"));
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public long readLong() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            long val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public double readDouble() {
            boolean sign = true;
            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+';
                next = read();
            }

            long val = 0;
            while (next >= '0' && next <= '9') {
                val = val * 10 + next - '0';
                next = read();
            }
            if (next != '.') {
                return sign ? val : -val;
            }
            next = read();
            long radix = 1;
            long point = 0;
            while (next >= '0' && next <= '9') {
                point = point * 10 + next - '0';
                radix = radix * 10;
                next = read();
            }
            double result = val + (double) point / radix;
            return sign ? result : -result;
        }

        public String readString(StringBuilder builder) {
            skipBlank();

            while (next > 32) {
                builder.append((char) next);
                next = read();
            }

            return builder.toString();
        }

        public String readString() {
            defaultStringBuf.setLength(0);
            return readString(defaultStringBuf);
        }

        public int readLine(char[] data, int offset) {
            int originalOffset = offset;
            while (next != -1 && next != '\n') {
                data[offset++] = (char) next;
                next = read();
            }
            return offset - originalOffset;
        }

        public int readString(char[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (char) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public int readString(byte[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (byte) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public char readChar() {
            skipBlank();
            char c = (char) next;
            next = read();
            return c;
        }

        public void flush() {
            try {
                os.write(cache.toString().getBytes(charset));
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        public boolean hasMore() {
            skipBlank();
            return next != -1;
        }
    }

    public static class Debug {
        private boolean allowDebug;

        public Debug(boolean allowDebug) {
            this.allowDebug = allowDebug;
        }

        public void assertTrue(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (!flag) {
                fail();
            }
        }

        public void fail() {
            throw new RuntimeException();
        }

        public void assertFalse(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (flag) {
                fail();
            }
        }

        private void outputName(String name) {
            System.out.print(name + " = ");
        }

        public void debug(String name, int x) {
            if (!allowDebug) {
                return;
            }

            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, long x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, double x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, int[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, long[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, double[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, Object x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, Object... x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.deepToString(x));
        }
    }

    public static class Randomized {
        static Random random = new Random(12345678);

        public static double nextDouble(double min, double max) {
            return random.nextDouble() * (max - min) + min;
        }

        public static void randomizedArray(int[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                int tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(long[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                long tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(double[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                double tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(float[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                float tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static <T> void randomizedArray(T[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                T tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static int nextInt(int l, int r) {
            return random.nextInt(r - l + 1) + l;
        }
    }

    public static class Mathematics {
        public static int ceilPowerOf2(int x) {
            return 32 - Integer.numberOfLeadingZeros(x - 1);
        }

        public static int floorPowerOf2(int x) {
            return 31 - Integer.numberOfLeadingZeros(x);
        }

        public static long modmul(long a, long b, long mod) {
            return b == 0 ? 0 : ((modmul(a, b >> 1, mod) << 1) % mod + a * (b & 1)) % mod;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static int gcd(int a, int b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static int gcd0(int a, int b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static int extgcd(int a, int b, int[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                int g = extgcd0(b, a, coe);
                int tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static int extgcd0(int a, int b, int[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            int g = extgcd0(b, a % b, coe);
            int n = coe[0];
            int m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static long gcd(long a, long b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static long gcd0(long a, long b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static long extgcd(long a, long b, long[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                long g = extgcd0(b, a, coe);
                long tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static long extgcd0(long a, long b, long[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            long g = extgcd0(b, a % b, coe);
            long n = coe[0];
            long m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get y where x * y = 1 (% mod)
         */
        public static int inverse(int x, int mod) {
            return pow(x, mod - 2, mod);
        }

        /**
         * Get x^n(% mod)
         */
        public static int pow(int x, int n, int mod) {
            int bit = 31 - Integer.numberOfLeadingZeros(n);
            long product = 1;
            for (; bit >= 0; bit--) {
                product = product * product % mod;
                if (((1 << bit) & n) != 0) {
                    product = product * x % mod;
                }
            }
            return (int) product;
        }

        public static long longpow(long x, long n, long mod) {
            if (n == 0) {
                return 1;
            }
            long prod = longpow(x, n >> 1, mod);
            prod = modmul(prod, prod, mod);
            if ((n & 1) == 1) {
                prod = modmul(prod, x, mod);
            }
            return prod;
        }

        /**
         * Get x % mod
         */
        public static int mod(int x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return x;
        }

        public static int mod(long x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return (int) x;
        }

        /**
         * Get n!/(n-m)!
         */
        public static long permute(int n, int m) {
            return m == 0 ? 1 : n * permute(n - 1, m - 1);
        }

        /**
         * Put all primes less or equal to limit into primes after offset
         */
        public static int eulerSieve(int limit, int[] primes, int offset) {
            boolean[] isComp = new boolean[limit + 1];
            int wpos = offset;
            for (int i = 2; i <= limit; i++) {
                if (!isComp[i]) {
                    primes[wpos++] = i;
                }
                for (int j = offset, until = limit / i; j < wpos && primes[j] <= until; j++) {
                    int pi = primes[j] * i;
                    isComp[pi] = true;
                    if (i % primes[j] == 0) {
                        break;
                    }
                }
            }
            return wpos - offset;
        }

        /**
         * Round x into integer
         */
        public static int intRound(double x) {
            if (x < 0) {
                return -(int) (-x + 0.5);
            }
            return (int) (x + 0.5);
        }

        /**
         * Round x into long
         */
        public static long longRound(double x) {
            if (x < 0) {
                return -(long) (-x + 0.5);
            }
            return (long) (x + 0.5);
        }
    }
}


import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.*;

public class CF1158 {
    public static void main(String[] args) throws Exception {
        boolean local = System.getProperty("ONLINE_JUDGE") == null;
        boolean async = false;

        Charset charset = Charset.forName("ascii");

        FastIO io = local ? new FastIO(new FileInputStream("D:\\DATABASE\\TESTCASE\\Code.in"), System.out, charset) : new FastIO(System.in, System.out, charset);
        Task task = new Task(io, new Debug(local));

        if (async) {
            Thread t = new Thread(null, task, "dalt", 1 << 27);
            t.setPriority(Thread.MAX_PRIORITY);
            t.start();
            t.join();
        } else {
            task.run();
        }

        if (local) {
            io.cache.append("\n\n--memory -- \n" + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) >> 20) + "M");
        }

        io.flush();
    }

    public static class Task implements Runnable {
        final FastIO io;
        final Debug debug;
        int inf = (int) 1e8;
        int mod = (int) 1e9 + 7;

        public int mod(int val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return val;
        }

        public int mod(long val) {
            val %= mod;
            if (val < 0) {
                val += mod;
            }
            return (int) val;
        }

        int bitAt(int x, int i) {
            return (x >> i) & 1;
        }

        int bitAt(long x, int i) {
            return (int) ((x >> i) & 1);
        }

        public Task(FastIO io, Debug debug) {
            this.io = io;
            this.debug = debug;
        }

        @Override
        public void run() {
            solve();
        }

        public void solve() {
            int n = io.readInt();
            int m = io.readInt();
            int[] boys = new int[n];
            int[] girls = new int[m];

            int max = 0;
            TreeMap<Integer, Integer> set = new TreeMap<>();
            HashMap<Integer, Integer> equalSet = new HashMap<>();
            long total = 0;
            for (int i = 0; i < n; i++) {
                boys[i] = io.readInt();
                total += boys[i] * (long) m;
                set.put(boys[i], m - 1);
                equalSet.put(boys[i], equalSet.getOrDefault(boys[i], 0) + 1);
                max = Math.max(boys[i], max);
            }

            for (int i = 0; i < m; i++) {
                girls[i] = io.readInt();

                if (girls[i] < max) {
                    io.cache.append(-1);
                    return;
                }
                if (equalSet.containsKey(girls[i])) {
                    int count = equalSet.get(girls[i]);
                    if (count == 1) {
                        equalSet.remove(girls[i]);
                    } else {
                        equalSet.put(girls[i], count - 1);
                    }
                    continue;
                }
                Integer min = set.floorKey(girls[i]);
                total += girls[i] - min;
                Integer count = set.get(min);
                if (count == 1) {
                    set.remove(min);
                } else {
                    set.put(min, count - 1);
                }
            }

            io.cache.append(total);
        }
    }

    public static class FastIO {
        public final StringBuilder cache = new StringBuilder();
        private final InputStream is;
        private final OutputStream os;
        private final Charset charset;
        private StringBuilder defaultStringBuf = new StringBuilder(1 << 8);
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastIO(InputStream is, OutputStream os, Charset charset) {
            this.is = is;
            this.os = os;
            this.charset = charset;
        }

        public FastIO(InputStream is, OutputStream os) {
            this(is, os, Charset.forName("ascii"));
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public long readLong() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            long val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public double readDouble() {
            boolean sign = true;
            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+';
                next = read();
            }

            long val = 0;
            while (next >= '0' && next <= '9') {
                val = val * 10 + next - '0';
                next = read();
            }
            if (next != '.') {
                return sign ? val : -val;
            }
            next = read();
            long radix = 1;
            long point = 0;
            while (next >= '0' && next <= '9') {
                point = point * 10 + next - '0';
                radix = radix * 10;
                next = read();
            }
            double result = val + (double) point / radix;
            return sign ? result : -result;
        }

        public String readString(StringBuilder builder) {
            skipBlank();

            while (next > 32) {
                builder.append((char) next);
                next = read();
            }

            return builder.toString();
        }

        public String readString() {
            defaultStringBuf.setLength(0);
            return readString(defaultStringBuf);
        }

        public int readLine(char[] data, int offset) {
            int originalOffset = offset;
            while (next != -1 && next != '\n') {
                data[offset++] = (char) next;
                next = read();
            }
            return offset - originalOffset;
        }

        public int readString(char[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (char) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public int readString(byte[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (byte) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public char readChar() {
            skipBlank();
            char c = (char) next;
            next = read();
            return c;
        }

        public void flush() {
            try {
                os.write(cache.toString().getBytes(charset));
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        public boolean hasMore() {
            skipBlank();
            return next != -1;
        }
    }

    public static class Debug {
        private boolean allowDebug;

        public Debug(boolean allowDebug) {
            this.allowDebug = allowDebug;
        }

        public void assertTrue(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (!flag) {
                fail();
            }
        }

        public void fail() {
            throw new RuntimeException();
        }

        public void assertFalse(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (flag) {
                fail();
            }
        }

        private void outputName(String name) {
            System.out.print(name + " = ");
        }

        public void debug(String name, int x) {
            if (!allowDebug) {
                return;
            }

            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, long x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, double x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, int[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, long[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, double[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, Object x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, Object... x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.deepToString(x));
        }
    }

    public static class Randomized {
        static Random random = new Random(12345678);

        public static double nextDouble(double min, double max) {
            return random.nextDouble() * (max - min) + min;
        }

        public static void randomizedArray(int[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                int tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(long[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                long tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(double[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                double tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static void randomizedArray(float[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                float tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static <T> void randomizedArray(T[] data, int from, int to) {
            to--;
            for (int i = from; i <= to; i++) {
                int s = nextInt(i, to);
                T tmp = data[i];
                data[i] = data[s];
                data[s] = tmp;
            }
        }

        public static int nextInt(int l, int r) {
            return random.nextInt(r - l + 1) + l;
        }
    }

    public static class Mathematics {
        public static int ceilPowerOf2(int x) {
            return 32 - Integer.numberOfLeadingZeros(x - 1);
        }

        public static int floorPowerOf2(int x) {
            return 31 - Integer.numberOfLeadingZeros(x);
        }

        public static long modmul(long a, long b, long mod) {
            return b == 0 ? 0 : ((modmul(a, b >> 1, mod) << 1) % mod + a * (b & 1)) % mod;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static int gcd(int a, int b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static int gcd0(int a, int b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static int extgcd(int a, int b, int[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                int g = extgcd0(b, a, coe);
                int tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static int extgcd0(int a, int b, int[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            int g = extgcd0(b, a % b, coe);
            int n = coe[0];
            int m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static long gcd(long a, long b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static long gcd0(long a, long b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static long extgcd(long a, long b, long[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                long g = extgcd0(b, a, coe);
                long tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static long extgcd0(long a, long b, long[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            long g = extgcd0(b, a % b, coe);
            long n = coe[0];
            long m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get y where x * y = 1 (% mod)
         */
        public static int inverse(int x, int mod) {
            return pow(x, mod - 2, mod);
        }

        /**
         * Get x^n(% mod)
         */
        public static int pow(int x, int n, int mod) {
            int bit = 31 - Integer.numberOfLeadingZeros(n);
            long product = 1;
            for (; bit >= 0; bit--) {
                product = product * product % mod;
                if (((1 << bit) & n) != 0) {
                    product = product * x % mod;
                }
            }
            return (int) product;
        }

        public static long longpow(long x, long n, long mod) {
            if (n == 0) {
                return 1;
            }
            long prod = longpow(x, n >> 1, mod);
            prod = modmul(prod, prod, mod);
            if ((n & 1) == 1) {
                prod = modmul(prod, x, mod);
            }
            return prod;
        }

        /**
         * Get x % mod
         */
        public static int mod(int x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return x;
        }

        public static int mod(long x, int mod) {
            x %= mod;
            if (x < 0) {
                x += mod;
            }
            return (int) x;
        }

        /**
         * Get n!/(n-m)!
         */
        public static long permute(int n, int m) {
            return m == 0 ? 1 : n * permute(n - 1, m - 1);
        }

        /**
         * Put all primes less or equal to limit into primes after offset
         */
        public static int eulerSieve(int limit, int[] primes, int offset) {
            boolean[] isComp = new boolean[limit + 1];
            int wpos = offset;
            for (int i = 2; i <= limit; i++) {
                if (!isComp[i]) {
                    primes[wpos++] = i;
                }
                for (int j = offset, until = limit / i; j < wpos && primes[j] <= until; j++) {
                    int pi = primes[j] * i;
                    isComp[pi] = true;
                    if (i % primes[j] == 0) {
                        break;
                    }
                }
            }
            return wpos - offset;
        }

        /**
         * Round x into integer
         */
        public static int intRound(double x) {
            if (x < 0) {
                return -(int) (-x + 0.5);
            }
            return (int) (x + 0.5);
        }

        /**
         * Round x into long
         */
        public static long longRound(double x) {
            if (x < 0) {
                return -(long) (-x + 0.5);
            }
            return (long) (x + 0.5);
        }
    }
}