#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, a, b, c, mn;
  cin >> n >> a >> b >> c;
  mn = min(a, min(b, c));
  if (mn == b || mn == a || n == 1)
    cout << min(a, b) * (n - 1);
  else
    cout << min(a, b) + c * (n - 2);
}
