#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <fstream>
#include <iostream>
#include <map>
#include <queue>
#include <string>
#include <stack>
#include <vector>
#include <set>
#include <utility>
using namespace std;
typedef long long ll;

int main(){
    double x,y;
    cin >> x >> y;

    x *= 1000;
    y *= 1000;

    ll h;
    cin >> h;

    int cnt = 0;
    while(max(x,y) > h){
        if(x < y)swap(x,y);

        if(y > h){
            y /= 2;
            h *= 2;
        }
        else if(x > h){
            x /= 2;
            h *= 2;
        }

        cnt++;
    }

    cout << cnt << endl;
}