#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <stdio.h>
#include <cstring>
#include <queue>
#include <stack>
#include <functional>
#include <math.h>
#include <iomanip>
using namespace std;
#define Would
#define you
const int INF = 999999999;
const int MOD = 1e9 + 7;
double pi = 3.1415926535897932384626;

int main() {
	long long n, ans = 0, mon = 1;
	cin >> n;
	while (mon < n) {
		mon *= 2;
		++ans;
	}
	cout << ans << endl;
}