#include <iostream>
using namespace std;

int main() {
  long double x, y, h;
  cin >> x >> y >> h;
  x *= 1000; y*= 1000;
  long double xx = x, yy = y, hh = h;
  int s = 0;
  int t = 0;
  while(x > h) {
    x /= 2;
    h *= 2;
    s++;
  }
  while(y > h) {
    y /= 2;
    h *= 2;
    s++;
  }
  while(yy > h) {
    yy /= 2;
    hh *= 2;
    t++;
  }
  while(xx > h) {
    xx /= 2;
    hh *= 2;
    t++;
  }
  cout << max(s, t) << endl;
}