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