Make a function that checks whether a knight can reach a certain position on a chess board from a given starting position within 3 moves. Position denoted as (Int,Int)

kightsQuest.hs

import qualified Control.Monad as M

type KnightPos = (Int,Int)

moveKnight :: KnightPos -> [KnightPos]
moveKnight (c,r) = do
  (c',r') <- [(c+2,r-1),(c+2,r+1),(c-2,r-1),(c-2,r+1)
             ,(c+1,r-2),(c+1,r+2),(c-1,r-2),(c-1,r+2)
             ]
  M.guard (c' `elem` [1..8] && r' `elem` [1..8])
  return (c',r')

canReachIn3 :: KnightPos -> KnightPos -> Bool
canReachIn3 start target = target `elem` in3 start

Can your programming language do this in 14 lines. Note that this isn't code golf code. This is the readable version with (optional) type annotations