Tower of Hanoy

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Tower of Hanoy is a solitaire card game which only uses 9 playing cards. It is based on the actual Tower of Hanoi game, where the object is to transfer discs from one peg to another without disturbing their order. Whether the misspelling of the name Hanoi is accidental or intentional is not known.

First, nine cards, numbered Ace to 9 are removed from the deck. Although it is not necessary, it is a general idea that they have to be of the same suit. Then, they are dealt in 3 columns of three cards each, overlapping either in an upward or downward direction.

As in the original Tower of Hanoi game, the player should follow the following rules:

  • Only the top card of each column can be moved.
  • Only one card can be moved at a time.
  • A card can never be put over another card lower in rank.
  • An empty column can be filled by a top card from either of the other two columns.

As in the original, the game is won when all nine cards arranged vertically in one column from the nine at the bottom to the ace at the top. A nine-disk version of the original game takes 511 moves to complete. Considering that the cards never start the same way the disks are in the original game, it takes far fewer moves to finish this game.

This article explains the game with the cards overlapping to avoid confusion. There are versions of the game where the cards are laid out in a 3x3 grid and the player aims to make a vertical column with the direction of play either upwards or downwards; the rules above can be modified to suit the direction and/or manner of play.