#include <bits/stdc++.h>
#define PI 3.14159265359
using namespace std;
const int64_t mod = 1e9 + 7;

int main() {
	int N;
	cin >> N;

	int cnt = 0;
	int n = 1;
	while (1) {
		if (n >= N) {
			cout << cnt << endl;
			return 0;
		}

		n *= 2;
		cnt++;
	}
}