#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<bitset>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<deque>
#include<list>
#include<iomanip>
#include<cmath>
#include<cstring>
#include<functional>
#include<cstdio>
#include<cstdlib>
#include<unordered_map>
#include<unordered_set>
using namespace std;

#define repr(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rep(i, n) repr(i, 0, n)
#define INF 2e9
#define MOD 1000000007
//#define MOD 998244353
#define LINF (long long)4e18
#define jck 3.141592
#define PI acos(-1.0);

const double EPS = 1e-10;

using ll = long long;
using Pi = pair<int,int>;
using Pl = pair<ll,ll>;


int main(){
    double x,y; cin >> x >> y;
    ll h; cin >> h;
    x *= 1000;
    y *= 1000;
    ll ans = 0;
    if(x > y) swap(x,y);
    while(x > h){
        x /= 2;
        h *= 2;
        ans++;
    }
    while(y > h){
        y /= 2;
        h *= 2;
        ans++;
    }
    cout << ans << endl;
}