#include<bits/stdc++.h>
using namespace std;
int main()
{
	int m,n,h,k=0,s=0;
	cin>>m>>n>>h;
	for(;k<=h-m;){
		k=k+m-n;
		s++;
	}
	cout<<s;
return 0;

}

/**************************************************************
	Problem: 1074
	User: houshanglin
	Language: C++
	Result: Wrong Answer
****************************************************************/