#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 + 10;
long long int A[MAXN], B[MAXN];
long long int sumA, sumB;
int N, M;
int main() {
  cin.sync_with_stdio(false);
  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];
  sort(A, A + M);
  sort(B, B + N);
  long long int t1 = sumB, t2 = sumA;
  for (int i = 0; i < M - 1; i++) {
    t1 += min(sumB, A[i]);
  }
  for (int i = 0; i < N - 1; i++) {
    t2 += min(sumA, B[i]);
  }
  cout << min(t1, t2) << endl;
  return 0;
}
