typedef long long ll;
typedef long double ld;
#include <bits/stdc++.h>
using namespace std;

int main() {
    ld x,y,h;
    std::cin >> x>>y>>h;
    h/= 1000.0;
    vector<ld> a = {x,y};
    bool ok = false;
    
    ll cnt = 0;
    while(true){
        sort(a.begin(),a.end());
        if(a[0]<=h){
            ok = true;
        }
        
        if(a[ok]>h){
            a[ok] /= 2;
            h *= 2;
        }else{
            break;
        }
        cnt++;
    }
    std::cout << cnt << std::endl;
    
}