#include<bits/stdc++.h>
using namespace std;
using ll=long long;

ll solve1(ll N,ll A,ll B){
    return min({-A*(N-1)-B*(N%2),-B*N+A*(N-1),(1-N%2)*(-B*N+A*(N-1)+2*B-4*A)});
}

int main(){
    ll N,A,B;
    cin>>N>>A>>B;
    cout<<solve1(N,A,B)<<endl;
    return 0;
}