#include <iostream>
using namespace std;

int main()
{
	long long k, a, b, m;

	cin >> k >> a >> b;

	if (k > a && b - a > 2) {
		long long t = (k - a + 1) / 2;
		m = a + (b - a) * t + (k - a + 1 - t * 2);
	}
	else
		m = k + 1;

	cout << m << endl;

	return 0;
}