#include<iostream>
#include<string>
#include<algorithm>
#include<cmath>
#include<iomanip>
#include<cstring>
#include<map>
#include<vector>
#include<queue>
#include<utility>
using namespace std;
typedef long long int ll;

int main(){

  int n, num=1, ans=0;
  cin >> n;

  while(n){
    if(n<=num){
      cout << ans << endl;
      return 0;
    }
    num*=2;
    ans++;
  }

  return 0;
}