#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <cmath>
#include <iomanip>
#include <stack>
#include <queue>
#include <numeric>
#include <map>
#include <unordered_map>
#include <set>
#include <fstream>
#include <chrono>
#include <random>
#include <bitset>
//#include <atcoder/all>
#include <sstream>
#define rep(i,n) for(int i=0;i<(n);i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) ((int)(x).size())
#define pb push_back
using ll = long long;
using namespace std;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
ll gcd(ll a, ll b) {return b?gcd(b,a%b):a;}
ll lcm(ll a, ll b) {return a/gcd(a,b)*b;}

ll f(ll a,ll b,ll n,ll m){
  ll np = min(2*m,n-1);
  ll pp = n-1-np;
  ll p = n-m;
  ll res = -a*(np-pp)-b*(p-m);
  return res;
}

int main(){
  ll N,A,B; cin >> N >> A >> B;
  ll l = 0, r = N/2;
  while(abs(l-r)>10000){
    ll m1 = (l+l+r)/3;
    ll m2 = (l+r+r)/3;
    ll f1 = f(A,B,N,m1);
    ll f2 = f(A,B,N,m2);
    if(f1<f2) r=m2;
    else l=m1;
  }
  ll ans = 1LL<<60;
  for(ll x=l;x<=r;x++){
    chmin(ans,f(A,B,N,x));
  }
  cout << ans << endl;
  return 0;
}