#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  int choice;
  int n;
  cin >> n;
  n--;
  if (!n) {
    cout << "0" << endl;
    return 0;
  }
  cin >> a >> b >> c;
  if (a <= c && a <= b)
    choice = 1;
  else if (b < a && b < c)
    choice = 2;
  else
    choice = 3;
  if (choice == 1)
    cout << n * a << endl;
  else if (choice == 2)
    cout << n * b << endl;
  else {
    int tmp = min(a, b);
    cout << tmp + (n - 1) * c << endl;
  }
  return 0;
}
