#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    ll x, y, h;
    cin >> x >> y >> h;
    x *= 1000;
    y *= 1000;
    if (x > y) swap(x, y);

    ll ans = 0;
    while (x > h) {
        x >>= 1;
        h <<= 1;
        ++ans;
    }

    while (y > h) {
        y >>= 1;
        h <<= 1;
        ++ans;
    }

    cout << ans << "\n";
    return 0;
}