#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main(){
	ll k,a,b,ans=1,bis=1;
	cin>>k>>a>>b;
	if(b>=a+2){//2回交換
		k-=a-bis;
		ans=a;
		ll cost=k/2;
		ans+=cost*(b-a);
		if(k%2==1)ans++;
	}
	else{
		ans+=k;
	}
	cout<<ans<<endl;

}
