#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
long long a[maxn], b[maxn];
int main() {
  int m, n;
  long long sum1 = 0, sum2 = 0, max1 = 0, max2 = 0, t1, t2;
  scanf("%d%d", &m, &n);
  for (int i = 1; i <= m; i++) {
    scanf("%lld", &a[i]);
    sum1 += a[i];
    if (a[i] > max1) {
      t1 = i;
      max1 = a[i];
    }
  }
  for (int i = 1; i <= n; i++) {
    scanf("%lld", &b[i]);
    sum2 += b[i];
    if (b[i] > max2) {
      t2 = i;
      max2 = b[i];
    }
  }
  long long ans1 = sum1 * n, ans2 = sum2 * m;
  for (int i = 1; i <= m; i++) {
    if (i != t1 && a[i] < sum2) ans2 = ans2 - sum2 + a[i];
  }
  for (int i = 1; i <= n; i++) {
    if (i != t2 && b[i] < sum1) ans1 = ans1 - sum1 + b[i];
  }
  printf("%lld\n", min(ans1, ans2));
  return 0;
}
