#pragma GCC optimize ("O3","unroll-loops")
#pragma GCC target("avx512f")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ll n, a, b, c1, c2, ans = 1ll << 62;
    cin >> n >> a >> b;
    c1 = n / 2, c2 = n - c1;
    int r = n / 2;
    for(ll i = 0; i <= r; i++){
        ans = min(ans, a * (-(i << 2) + n - 1) + b * (-n + (i << 1)));
    }
    cout << ans << '\n';
}