For a checkers board [[R|B|E, ...], ...] where
- R represents a red piece
- B represents a black piece
- E represents an empty space
determine if any piece is in danger of attack.
Adapted from a solution I wrote in Q. Wanted to see how the array-centric concepts from APL/J/K/Q worked in Haskell. Additionally benefits from ADTs and Monads of course. Attempted to be as tacit as possible. Presented as a fun curiosity.