#include <bits/stdc++.h>
using namespace std;
struct abc {
  long long int c, x, y;
};
bool compare(abc a1, abc a2) {
  if (a1.x == a2.x) return a1.y > a2.y;
  return a1.x < a2.x;
}
const long long int mod = 1e9 + 7;
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  long long int n, a, b, c, ans = 0;
  cin >> n >> a >> b >> c;
  n--;
  if (n > 0) {
    ans += min(a, b);
    long long int x = min(ans, c);
    ans += (n - 1) * x;
  }
  cout << ans;
}
