#include <bits/stdc++.h>
using namespace std;
#define int long long

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