I have the following function which takes a list and returns two sublists split at a given element n. However, I only need to split it in half, with odd length lists having
In a real program you should probably use
splitlist :: [a] -> ([a], [a])
splitlist xs = splitAt ((length xs + 1) `div` 2) xs
(i.e. something along the lines of dreamcrash's answer.)
But if, for learning purposes, you're looking for an explicitly recursive solution, study this:
splitlist :: [a] -> ([a], [a])
splitlist xs = f xs xs where
f (y : ys) (_ : _ : zs) =
let (as, bs) = f ys zs
in (y : as, bs)
f (y : ys) (_ : []) = (y : [], ys)
f ys [] = ([], ys)