#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  int n;
  cin >> n >> a >> b >> c;
  int x1 = min(a, b);
  int x2 = min(x1, c);
  int sum = 0;
  int loca = 0;
  for (int i = 0; i < n - 1; i++) {
    if (loca == 0)
      sum += x1, loca = 1;
    else
      sum += x2;
  }
  cout << sum << endl;
  return 0;
}
