#include<bits/stdc++.h>
using namespace std;
int main(){
int i,m,n,h,s=0;
cin>>m>>n>>h;
for(i=1;1;i++){
s+=m;
if(s>=h){
cout<<i;
break;
}
s-=n;
}
return 0;}
/**************************************************************
Problem: 1074
User: fzy001
Language: C++
Result: Accepted
Time:20 ms
Memory:2072 kb
****************************************************************/