#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,h=0,i=1;
	cin>>n;
	while(i<n){
		if(n%2==0){
			h++;
		}
		i=i*2;
	}
	cout<<h;
	
}

/**************************************************************
	Problem: 1244
	User: zhengzihao3
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2072 kb
****************************************************************/