#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main()
{
    int M, N;
    cin >> M >> N;
    vector<pair<int, int>> vagasok(N + M - 2);

    int temp;
    for(int i = 0; i < M-1; i++){
        cin >> temp;
        vagasok[i] = {temp, 1};
    }
    for(int i = 0; i < N-1; i++){
        cin >> temp;
        vagasok[M-1 + i] = {temp, 2};
    }

    sort(vagasok.begin(), vagasok.end(), greater<pair<int, int>>{});

    long long megoldas = 0;
    int db1 = 1, db2 = 1;

    for(int i = 0; i < vagasok.size(); i++){
        if(vagasok[i].second == 1){
            megoldas += vagasok[i].first * db2;
            db1++;
        }
        else{
            megoldas += vagasok[i].first * db1;
            db2++;
        }
    }
    cout << megoldas << endl;
    return 0;
}