//--------------------

//Edouard Moureaux

//March 2016

//

// Problem URL:

// https://www.hackerrank.com/challenges/super-queens-on-a-chessboard

//--------------------

namespace FunctionalProgramming.Recursion

​

module Super_Queens = 

    open System

​

    let (|Danger|Safe|) (xQ, yQ) (x ,y) =

        let difX = (x - xQ) |> float

        let difY = (y - yQ) |> float

​

        if x = xQ then Danger (x, y)

        elif y = yQ then Danger (x, y)

        elif abs difX + abs difY <= 4. then Danger (x, y)

        else Safe (x,y)

​

​