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