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