using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(CalCulate(-12));

    }

    public static int CalCulate(int num)

    {

        if(num<=0)

        {

            return -1;

        }

        if(num%2==0)

        {

            return num*num;

        }

        else

        {

            return num*num*num;

        }

    }

}