# include <iostream>
# include <algorithm>
# include <vector>
# include <string>
# include <set>
# include <map>
# include <cmath>
# include <iomanip>
# include <functional>
# include <utility>
# include <stack>
# include <queue>
# include <list>
using namespace std;
using LL = long long;
constexpr int MOD = 1000000000 + 7;
//足し算してオーバーフローで死なないように確認しようね
constexpr int INF = 1000000000;
const double PI = acos(-1);

int main() {
	int n;
	cin >> n;
	int num = 1;
	if (n == 1) {
		cout << 0 << endl;
		return 0;
	}
	for (int i = 1;; i++) {
		num *= 2;
		if (num >= n) {
			cout << i << endl;
			return 0;
		}
	}
}