#include <iostream>

using namespace std;

int main()
{
    long long int a;
    while (cin >> a)
    {
        if( (a/2) % 2 == 0 )
            cout << ( (a/4)*(a/4) ) ;
        else
            cout << ( ((a/2)/2+1)*((a/2)/2) ) ;
    }

        return 0;
}