#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <cstring>
#include <string>
#include <algorithm>
#include <cmath>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <functional>

typedef long long int ll;
using namespace std;
#define INF 1234567890
#define N 200000

const int LIMIT = 1e+9;
int n, m;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);

	int a, b, v;
	cin >> a >> b >> v;
	
	int div = (v - b) / (a - b);
	int mod = (v - b) % (a - b);

	if (mod) {
		cout << div + 1;
	}
	else {
		cout << div;
	}

	return 0;
}