#include<bits/stdc++.h>
#define ll long long
using namespace std;
int main()
{
	ll k,n,m,ans=0;
	cin>>k>>n>>m;
	if(k<n||n+2>=m)
	{
		cout<<k+1<<endl;
		return 0;
	}
	ans+=n;
	k-=n-1;
//	cout<<ans<<' '<<k<<endl;
	ans+=k%2;
	ans+=k/2*(m-n);
	cout<<ans<<endl;
	return 0;
}