#include <iostream>
#include <algorithm>
#include <cmath>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <stdio.h>

using namespace std;

typedef long long ll;

int main() {
	ll k, a, b;
	cin >> k >> a >> b;
	ll sum = 1;
	if (b - a <= 2) cout << k + sum << endl;
	else {
		k = k - (a-sum);
		sum = a;
		ll t = k / 2;
		sum += (b - a)*t;
		ll tt = k % 2;
		sum += tt;
		cout << sum << endl;
	}
	return 0;
}