#include <bits/stdc++.h>
using namespace std;

#define int long long
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

signed main(){
	int v, t, p;

	cin >> v >> t >> p;

	int ans = (p+1)*v + 1;

	int tmp = ans-1;
	while(tmp >= t){
		int plus = tmp / t;
		ans += plus;
		tmp = plus + tmp%t;
	}
	cout << ans << endl;
	return 0;
}