#include <bits/stdc++.h>
using namespace std;
using lint     = long long;
const lint inf = 1LL << 60;
const lint mod = 1000000007;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    double x, y, h;
    cin >> x >> y >> h;
    x *= 1000;
    y *= 1000;
    if (x < y)
        swap(x, y);
    int ret = 0;
    while (y > h + 1e-10) {
        ret++;
        y /= 2;
        h *= 2;
    }
    while (x > h + 1e-10) {
        ret++;
        x /= 2;
        h *= 2;
    }
    cout << ret << "\n";
    return 0;
}