Tsianshidsi

Alternate Names

Tsyan-shizi or Tsyanshidzi (Picking Stones or Picking Stones Game); Wythoff's Game.

No. of Players

Two

Equipment

Any number of small counters are all that is required for the play of this game.

History

This game is likely very ancient, but is likely to originate from China. The Dutch mathematician W.A. Wythoff may have independently discovered it and published a mathematical analysis of it in 1907.

Objective

Tsianshidsi is commonly played as a normal play game, meaning that the person who removes the last counter or counters is the winner. It may also, however, be played as a misère game, where the player that is forced to remove the last counter loses the game.

Play

The counters are arranged into two distinct piles or rows. Players take turns removing one or more counters from one or both piles. If a player removes from both piles, the number of counters removed from each pile must be equal.

Strategy

Variations

Tsianshidsi is closely related and possibly ancestral to the game Nim and Nim-related games.

Grundy's Game starts with a single pile of counters. Two players alternate turns splitting a single pile into two piles of different sizes. The game ends when only piles of one and two counters remain, neither of which can be split unequally. The game is usually played as a normal play game, which means that the last person who can make an allowed move wins.

Sources