import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.io.IOException;
import java.util.Random;
import java.io.InputStream;

/**
 * Built using CHelper plug-in Actual solution is at the top
 * 
 * @author daltao
 */
public class Main {
    public static void main(String[] args) throws Exception {
        Thread thread = new Thread(null, new TaskAdapter(), "daltao", 1 << 27);
        thread.start();
        thread.join();
    }

    static class TaskAdapter implements Runnable {
        @Override
        public void run() {
            InputStream inputStream = System.in;
            OutputStream outputStream = System.out;
            FastInput in = new FastInput(inputStream);
            PrintWriter out = new PrintWriter(outputStream);
            TaskC solver = new TaskC();
            solver.solve(1, in, out);
            out.close();
        }
    }
    static class TaskC {
        public void solve(int testNumber, FastInput in, PrintWriter out) {
            int w = in.readInt();
            int h = in.readInt();
            int[] rowCost = new int[h];
            int[] colCost = new int[w];

            for (int i = 0; i < w; i++) {
                colCost[i] = in.readInt();
            }

            for (int i = 0; i < h; i++) {
                rowCost[i] = in.readInt();
            }

            Randomized.randomizedArray(rowCost, 0, rowCost.length);
            Randomized.randomizedArray(colCost, 0, colCost.length);
            Arrays.sort(rowCost);
            Arrays.sort(colCost);

            int rIndex = 0;
            int cIndex = 0;

            long cost = 0;
            while (rIndex < h || cIndex < w) {
                if (rIndex < h && (cIndex >= w || rowCost[rIndex] <= colCost[cIndex])) {
                    long need = w + 1 - cIndex;
                    cost += need * rowCost[rIndex];
                    rIndex++;
                } else {
                    long need = h + 1 - rIndex;
                    cost += need * colCost[cIndex];
                    cIndex++;
                }
            }

            out.println(cost);
        }

    }
    static class FastInput {
        private final InputStream is;
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastInput(InputStream is) {
            this.is = is;
        }

        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;
        }

    }
    static class Randomized {
        static Random random = new Random();

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

    }
}



Measured memory_bytes: 26680