#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, a, b, c;
  cin >> n;
  cin >> a;
  cin >> b;
  cin >> c;
  if (n == 1)
    cout << "0";
  else {
    cout << min(a, b) + (n - 2) * min(a, min(b, c));
  }
}
