#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
	ll k,a,b,ans;
	cin>>k>>a>>b;
	if(b<=a+2)ans=k+1;
	else ans=max(1ll,(k-a+1)/2*(b-a)+a+(k-a+1)%2);
	cout<<ans<<endl;
	return 0;
}