#include <iostream>

#define REP(i,a) for(int i=0; i<a; i++)

using namespace std;

int main ()
{
  int N;
  cin >> N;

  int press_count = 0;
  int cookies = 1;
  REP(i, 134217728) {
    if (cookies*2 <= N) {
      cookies *= 2;
      press_count++;
    }
    else break;
  }

  if (cookies < N) press_count++;
  cout << press_count << endl;

  return 0;
}