#include <bits/stdc++.h>
#define rep(i,n) for(int (i)=0;(i)<(int)(n);(i)++)
#define repeq(i,n) for(int (i)=0;(i)<=(int)(n);(i)++)
#define rep1(i,x,n) for(int (i)=(x);(i)<(int)(n);(i)++)
#define rep1eq(i,x,n) for(int (i)=(x);(i)<=(int)(n);(i)++)
#define rrep(i,x) for(int i=((int)(x)-1);i>=0;i--)
using namespace std;
using ll = long long;
using Int = long long;

const int MOD = 1000000007;
const ll INF = numeric_limits<ll>::max();
const int inf = 1e8;
//typedef pair<int,int> P;

//少数点表示
//cout << std::fixed << std::setprecision(14) <<double値

int main(){
    cin.tie( 0 ); ios::sync_with_stdio( false );
    ll x,y;
    double h;
    cin >> x >> y >> h;
    x *= 1000;
    y *= 1000;

    if(x > y) swap(x,y);
    ll count = 0;
    while(x > h){
        x /= 2;
        h *= 2;
        ++count;
    }
    while(y > h){
        y /= 2;
        h *= 2;
        ++count;
    }

    cout << count << endl;
    return 0;

}