#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int,int>;
#define rep(i,n) for(int i=0;i<n;i++)

const ll mod = ll(1e9) + 7;
const int INF = 1<<29;

int main(){
    double x,y,h;
    cin >> x >> y >> h;
    x *= 1000; y *= 1000;
    int ans = 0;
    while (max(x,y)>h){
        if (min(x,y)>h){
            if (min(x,y)==x) x /= 2.0;
            else y /= 2.0;
            h *= 2;
        }
        else if (max(x,y)>h){
            if (max(x,y)==x) x /= 2.0;
            else y /= 2.0;
            h *= 2;
        }
        ans++;
    }
    cout << ans << endl;
    return 0;
}