#include <iostream>
#include <sstream>
#include <vector>
#include <algorithm>
#include <string>
#include <functional>
#include <numeric>
#include <ctype.h>
#include <cstdlib>
#include <string.h>
#include <cmath>
#include <cstdio>
#include <map>
#include <queue>
#include <utility>

using namespace std;

const int INF = 1000000007;
const double PI = acos(-1.0);

int main()
{
	int N, cnt = 0, Bis = 1;
	cin >> N;

	if (N == 1)
	{
		cout << 0 << endl;
		return 0;
	}

	while (true)
	{
		if (N <= Bis * 2)
			break;
		Bis = Bis * 2;
		cnt++;
	}

	cout << cnt + 1 << endl;

}