#include <iostream>
using namespace std;
int main() {
	int N;
	cin >> N;
	int count = 0;
	int Bisket = 1;
	while (Bisket < N) {
		if (Bisket >= 2) {
			int B = Bisket / 2;
			Bisket += B * 2;
		}
		if (Bisket == 1)Bisket++;
		count++;
	}
	cout << count << endl;
	return 0;
}