#include<bits/stdc++.h>
using namespace std;
#define int long long
int n,num,m;
signed main()
{
	cin >> n;
	m = n;
	for(int i = 1;i <= m && n > 1;i++)
	{
		if(n % 2 == 1)
		{
			n--;
			num++;
		}
		else
		{
			n = n / 2;
			num++;
		}
	}
	cout << num;
	return 0;
}