#include <bits/stdc++.h>
using namespace std;
#define REP(i,n) for (int i = 0; i < (n); i++)
typedef long long ll;
// Welcome to my source code!

int main() {
    int n;
    cin >> n;
    int cnt = 0;
    for (ll biscuit = 1; biscuit < n;) {
        biscuit *= 2;
        cnt++;
    }
    cout << cnt << endl;
}