//
//  main.cpp
//  2869-01
//
//  Created by dhpark on 4/28/17.
//  Copyright © 2017 dhpark. All rights reserved.
//
//  달팽이는 올라가고 싶다

#include <cstdio>
int A, B, V, K ;
int main(int argc, const char * argv[]) {
  scanf("%d %d %d", &A, &B, &V);
  while (1) {
    V -= A ;
    K++ ;
    if(V <= 0) break ;
    V += B ;
  }
  printf("%d\n", K);
  return 0;
}