Problem Statement

Bogosort a list of numbers.

Bogosort simply shuffles a collection randomly until it is sorted. "Bogosort" is a perversely inefficient algorithm only used as an in-joke.
Its average run-time is   O(n!)   because the chance that any given shuffle of a set will end up in sorted order is about one in   n   factorial,   and the worst case is infinite since there's no guarantee that a random shuffling will ever produce a sorted sequence. Its best case is   O(n)   since a single pass through the elements may suffice to order them.

Pseudocode:

The Knuth shuffle may be used to implement the shuffle part of this algorithm.

Let's start with the solution:

bogo=: monad define
  whilst.  +./ 2 >/\ Ry  do. Ry=. (A.~ ?@!@#) y  end. Ry
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