#include<iostream>

using namespace std;

typedef unsigned long long int ull ;

ull A;
ull B;
ull C;

int main(void){
	
	cin >> A;
	cin >> B;
	cin >> C;
	
	int i = 1;
	ull money = 0;
	
	while(true){
		
		if(i % A == 0) money += B;
		else money+= 1 ;
		
		if(money >= C) break;
		
		i++ ;
	}
	
	
	cout << i << endl;
	
	
	
	
	
	return 0;}