Sorting a queue using same queue

Question

I have been asked this question and I think it's doable, However I am having a hard time coming up with an algorithm to do this. The restrictions is that you can not use any other data structure nor create another queue. Also you only can use enqueue, dequeue and peek (NOT a priority queue).

Thanx for contributing :)

Answer 1

BubbleSort using a queue:

n <- size of queue
repeat n times
  x <- dequeue item
  repeat (n-1) times
    y <- dequeue item
    if x < y then
      enqueue y
    else
      enqueue x
      x <- y
    end
  end
  enqueue x
end