#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  long long n, m, i, j, k, sa, sb, maxa, maxb, ans, ans1, ans2;
  cin >> n >> m;
  vector<long long> a(n), b(m);
  for (i = 0; i < n; i++) cin >> a[i];
  for (i = 0; i < m; i++) cin >> b[i];
  sa = accumulate(a.begin(), a.end(), 0LL);
  sb = accumulate(b.begin(), b.end(), 0LL);
  maxa = a[0];
  for (i = 1; i < n; i++) maxa = max(maxa, a[i]);
  ans1 = 0;
  for (i = 0; i < n; i++) {
    if (maxa == a[i]) {
      maxa = -1;
      ans1 += sb;
    } else
      ans1 += min(sb, a[i]);
  }
  maxb = b[0];
  for (i = 1; i < m; i++) maxb = max(maxb, b[i]);
  ans2 = 0;
  for (i = 0; i < m; i++) {
    if (maxb == b[i]) {
      maxb = -1;
      ans2 += sa;
    } else
      ans2 += min(sa, b[i]);
  }
  ans = min(ans1, ans2);
  cout << ans << "\n";
  return 0;
}
