#include <bits/stdc++.h>
using namespace std;
long long ma, mb;
long long suma, sumb;
long long a[100001], b[100001];
long long n, m;
long long ans = 0, ans1 = 0;
int main() {
  scanf("%d%d", &n, &m);
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    suma += a[i];
    ma = max(ma, a[i]);
  }
  for (int i = 1; i <= m; i++) {
    scanf("%d", &b[i]);
    sumb += b[i];
    mb = max(mb, b[i]);
  }
  sort(a + 1, a + 1 + n);
  sort(b + 1, b + 1 + m);
  ans = sumb;
  ans1 = suma;
  for (int i = 1; i <= n - 1; i++) {
    ans += min(sumb, a[i]);
  }
  for (int i = 1; i <= m - 1; i++) {
    ans1 += min(suma, b[i]);
  }
  printf("%lld", min(ans, ans1));
  return 0;
}
