#include<iostream>
#include<algorithm>
#include<vector>
#include<functional>
#include<string>
#include<cmath>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<cstdio>
using namespace std;
using ll = long long;
int main(){
  long double x, y, h;
  cin >> x >> y >> h;
  x *= 1000;
  y *= 1000;
  if(x > y){
    swap(x, y); 
  }
  int ans = 0;
  while(x > h) {
    x /= 2.0;
    h *= 2.0;
    ans++;
  }
  while(y > h) {
    y /= 2.0;
    h *= 2.0;
    ans++;
  }
  cout << ans << '\n';
  return 0;
}