/* -*- coding: utf-8 -*-
 *
 * 1010.cc:  No.1010 折って重ねて - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

/* typedef */

typedef long long ll;

/* global variables */

/* subroutines */

/* main */

int main() {
  ll x, y, h;
  scanf("%lld%lld%lld", &x, &y, &h);

  x *= 1000, y *= 1000;
  if (x > y) swap(x, y);

  int c = 0;
  while (x > h) {
    x = (x + 1) >> 1;
    h <<= 1;
    c++;
  }
  while (y > h) {
    y = (y + 1) >> 1;
    h <<= 1;
    c++;
  }

  printf("%d\n", c);
  return 0;
}