#include <iostream>

using namespace std;

long long n;
long long now;
long long x;
long long k;

int main () {
	
	freopen ("zhuan.in", "r", stdin);
	freopen ("zhuan.out", "w", stdout);
	
	cin >> n >> x >> k;
	
	for (int i = 1; i <= n; i++) {
		long long t = (now + x) / k;
//		cout << x << ' ' << t << endl;
		if (x == t) {
			break;
		}
		now = now + x - t;
	}
	
	cout << now << endl;
	
	return 0;
}