#include <bits/stdc++.h>
using namespace std;
bool fun(long long num) {
  float x = sqrt(num);
  return x - floor(x) == 0;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long t;
  t = 1;
  while (t--) {
    int n, a, b, c = 0, d = 0;
    cin >> n >> a >> b >> c;
    if (n == 1) {
      cout << 0;
    } else {
      n--;
      int x = min(a, b);
      d += x;
      n--;
      while (n--) {
        if (c < x) {
          d += c;
        } else {
          d += x;
        }
      }
      cout << d << ("\n");
    }
  }
  return 0;
}
