#include <bits/stdc++.h>
using namespace std;
int a[100100], b[100100];
int main() {
  int n, m;
  long long sumA = 0, sumB = 0;
  cin >> m >> n;
  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];
  }
  long long ansA, ansB, sum = 0;
  sort(a, a + m);
  sort(b, b + n);
  ansB = sumA;
  for (int i = 0; i < n - 1; i++) ansB += min(b[i] * 1LL, sumA);
  ansA = sumB;
  for (int i = 0; i < m - 1; i++) ansA += min(a[i] * 1LL, sumB);
  cout << min(ansA, ansB) << endl;
}
