Cards Game

Let us play a game of cards. As you all know there are 52 cards in a regular deck, but our deck is somewhat different. Our deck consists of N cards. Each card simply contains a unique number from 1 to N. Initially all the cards are kept on the table, facing up. Rob, the notorious kid, flipped some of the cards, i.e. made them face down. Now, your task is to print any valid sequence of magic operat