#include <iostream>
using namespace std;
int main(){
	long long int a,b,c,money,age;
	cin>>a>>b>>c;
	money=0;
	age=0;
	while(1){
	    age++;
		if(age%a==0)money+=b;
		else money+=1;
		if(money>=c)break;
	}
	cout<<age<<endl;
}