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