#include <bits/stdc++.h>
using namespace std;


int main(void){
    double a, b, c; cin >> a >> b >> c;
    a *= 1000;
    b *= 1000;
    if (a > b) swap(a, b);
    int ans = 0;
    while (c < a) {
        a /= 2;
        c *= 2;
        ans++;
    }
    while (c < b) {
        b /= 2;
        c *= 2;
        ans++;
    }
    cout << ans << endl;
}