• @[email protected]
    82•12 days ago

    After working at blizzard for 51 years, I finally found an elegant solution by using the power of recursion

    private bool IsEven(int number){
  if (number > 1) return IsEven(number - 2);
  if (number == 0) return true;
  if (number == 1) return false;
}
      • λλλ
        13•11 days ago

        Now see, you need the other method. IsNegativeEven()

        • @[email protected]
          7•11 days ago

          We can avoid expensive branches (gasp) by using some bitwise arithmetic to achieve the so-called “absolute value”, an advanced hacker technique I learnt at Blizzard. Also unlike c, c# is not enlightened enough to understand that my code is perfect so it complains about “not all code paths returning a value”.

          private bool IsEven(int number)
{
    number *= 1 - 2*(int)(((uint)number & 2147483648) >> 31);
    if (number > 1) return IsEven(number - 2);
    if (number == 0) return true;
    if (number == 1) return false;
    throw new Exception();
}
          • @[email protected]
            1•10 days ago

            Nice, now we just need another function to find odd numbers, cause not all numbers are even you know.

    • @[email protected]
      11•12 days ago

      I removed the tail recursion for you:

      private book IsEven(int number) {
    if(number > 1) return IsEven(number - 2) == true;
    if(number == 0) return true; 
    if(number == 2) return false;
}
      • @[email protected]English
        2•12 days ago

        I didn’t get this.

        Why return book? Does that have some Blizzard reference?
        And why would number == 2 ⇒ return false? This is a function for getting true when the number is even, right?

        • @[email protected]
          10•12 days ago

          Haha, you’re right. I’ve now learned two things:

          1. I should not write code on a mobile
          2. I should not become a proof reader

          At the end of the day i just wanted the function to be worse, by causing stack overflows