#include<stdio.h>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
#include <sstream>
#include <iostream>
#include <string>

using namespace std;

int main() {

	long long cnt = 1, ans = 0, N;
	cin >> N;
	while (1) {
		if (cnt >= N) {
			break;
		}
		cnt *= 2;
		ans++;
	}

	cout << ans << endl;

	return 0;
}