#include <iostream>
#include <string>
#include <cmath>
#include <vector>
#include <algorithm>
using namespace std;

int main(){
  int num,ans;
  cin>>num;
  ans=0;
  while(1){
    if(pow(2,ans)>=num){
        break;
    }
    ans++;
  }
  cout<<ans<<endl;
}