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