#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  int m, n;
  cin >> m >> n;
  int a[m], b[n];
  long long suma = 0, sumb = 0;
  for (int i = 0; i < m; ++i) {
    cin >> a[i];
    suma += a[i];
  }
  for (int i = 0; i < n; ++i) {
    cin >> b[i];
    sumb += b[i];
  }
  sort(a, a + m);
  sort(b, b + n);
  long long ansa = suma, ansb = sumb;
  for (int i = 0; i < n - 1; ++i) ansa += min(suma, (long long)b[i]);
  for (int i = 0; i < m - 1; ++i) ansb += min(sumb, (long long)a[i]);
  cout << min(ansa, ansb) << endl;
  return 0;
}
