#include <bits/stdc++.h>
#define endl '\n'
using namespace std;

double a, b, t;
int cnt = 3;

int main(){
	cin >> a >> b >> t;
	
	double curr = 0;
	
	if(a > t){
		cout << 1;
		return 0;
	} else if(b > t){
		cout << 2;
		return 0; 
	}
	
	curr = sqrt(a * a + b * b); // µÚÈýÏî 
	while(curr <= t){
		cnt++;
		a = b;
		b = curr;
		curr = sqrt(a * a + b * b);
	}
	
	cout << cnt;
	return 0;
}