#include <iostream>
using namespace std;
typedef long long ll;

int main()
{
    ll n, a, b;
    cin >> n >> a >> b;
    ll ans = min(-(n - 1) * a - (n % 2) * b, (n - 1) * a - b * n);
    if(n % 2 == 0)
    {
        ans = min(ans, -(n - 3) * a - b * 2);
    }
    cout << ans << endl;
}