#include <bits/stdc++.h>
using namespace std;
int m, n, a[111111], b[111111];
int main() {
  while (~scanf("%d%d", &m, &n)) {
    long long sum1 = 0, sum2 = 0;
    for (int i = 0; i < m; i++) scanf("%d", &a[i]), sum1 += a[i];
    for (int i = 0; i < n; i++) scanf("%d", &b[i]), sum2 += b[i];
    sort(a, a + m), sort(b, b + n);
    long long ans1 = sum2, ans2 = sum1;
    for (int i = 0; i < m - 1; i++) ans1 += min(sum2, 1ll * a[i]);
    for (int i = 0; i < n - 1; i++) ans2 += min(sum1, 1ll * b[i]);
    printf("%I64d\n", min(ans1, ans2));
  }
  return 0;
}
