#include <iostream>
#include <algorithm>
using namespace std;

struct Cut {
    int cost;
    int type; 
} p[4005];

bool cmp(const Cut &x, const Cut &y) {
    return x.cost > y.cost;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N, M;
    cin >> N >> M;

    int tot = 0;
    
    for (int i = 0; i < N - 1; ++i) {
        cin >> p[tot].cost;
        p[tot].type = 0;
        tot++;
    }
    
    for (int i = 0; i < M - 1; ++i) {
        cin >> p[tot].cost;
        p[tot].type = 1;
        tot++;
    }

    sort(p, p + tot, cmp);

    long long ans = 0;
    int cntH = 1; 
    int cntV = 1; 

    for (int i = 0; i < tot; ++i) {
        if (p[i].type == 0) {
            
            ans += 1LL * p[i].cost * cntV;
            cntH++;
        } else {
            
            ans += 1LL * p[i].cost * cntH;
            cntV++;
        }
    }
    cout << ans << endl;
    return 0;
}