#include<iostream>
#include<cmath>
using namespace std;

int tataku(int n)
{
	int temp1 = 1;
	int temp2 = n - 1;
	int temp3 = 0;
	while (temp2 > 0){
		temp2 -= temp1;	//食べた枚数を引く
		temp1 *= 2;		//乗算
		temp3++;		//回数
	}
	return temp3;
}

int main()
{
	int n;
	cin >> n;
	cout << tataku(n) << endl;
	//for (int n = 1; n <= 10; ++n) {
	//	cout << n << ": " << tataku(n) << endl;
	//}
	return 0;
}