排列排序

Created: November-22, 2018

也稱為 bogosort 。

import Data.List (permutations)

sorted::Ord a => [a] -> Bool
sorted (x:y:xs) = x <= y && sorted (y:xs)
sorted _        = True

psort::Ord a => [a] -> [a]
psort = head . filter sorted . permutations

極其低效（在今天的計算機上）。