Example application.

Here are the rules of the game:
 * Two players are dealt the same number of cards from a shuffled deck.
 * Each player takes it in turns to place their next card on a pile between them.
 * If the two top cards on the pile match in numeric value (e.g. 9 == 9), the last player
 * to place a card takes all the cards in the pile.
 *
 * The game continues until one player is out of cards.