#include <iostream>

using namespace std;

int main()
{
    int n;
    cin>>n;


if(n%2==1)
{
    cout<<0;
    return 0;
}

n/=2;
    while(n%2)
    {
        n/=2;

        if(n==1)
            break;
    }

    cout<<n;
    return 0;
}