#include <iostream>

using namespace std;

int main()
{
  int N;
  cin >> N;
  int sum = 1;

  if(N == 1){
    cout << 0 << endl;
    return 0;
  }
  for(int i=1;; ++i){
    sum *= 2;
    if(sum >= N){
      cout << i << endl;
      return 0;
    }
  }
}