#include <bits/stdc++.h>
using namespace std;
long long a[100001], b[100001], ans1, ans2, sum1, sum2;
int main() {
  int m, n;
  while (cin >> m >> n) {
    sum1 = sum2 = 0;
    for (int i = 0; i < m; i++) {
      scanf("%lld", &a[i]);
      sum1 += a[i];
    }
    for (int j = 0; j < n; j++) {
      scanf("%lld", &b[j]);
      sum2 += b[j];
    }
    sort(a, a + m);
    sort(b, b + n);
    ans1 = sum2;
    ans2 = sum1;
    for (int i = 0; i < m - 1; i++) ans1 += min(sum2, a[i]);
    for (int i = 0; i < n - 1; i++) ans2 += min(sum1, b[i]);
    cout << min(ans1, ans2) << endl;
  }
  return 0;
}
