#include<cstdio>
#include<iostream>
using namespace std;
typedef long long ll;
int k,a,b;ll ans;
int main(){
	scanf("%d%d%d",&k,&a,&b);
	if(a>b||k<a||a+1==b){printf("%d\n",k+1);return 0;}
	ans=a+1ll*(b-a)*((k-a+1)>>1);
	if((k-a+1)&1)ans++;
	printf("%lld\n",ans);
	return 0;
}