#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

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

    x *= 1000;
    y *= 1000;

    if (x > y) swap(x, y);

    int r = 0;

    while (x > h) x /= 2, h *= 2, r++;
    while (y > h) y /= 2, h *= 2, r++;

    cout << r << endl;

    return 0;
}