#include <bits/stdc++.h>
using namespace std;
using nagai = long long;
using ll = long long;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;
  int c = 0;
  int t = 1;
  while (t <= n) {
    n -= t, ++c, t *= 2;
  }
  if (n) ++c;
  cout << c << '\n';
  return 0;
}
