#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using Graph = vector<vector<int>>;
int main() {
  long long N; cin >>N;
  long long x = 1;
  long long count = 0;
  while(true) {
    N /= 2;
    count++;
    if(N == 0) {
      break;
    }
   
  }
  cout << count << endl;
}