2.2. Current System

Tic Tac Toe is a game where two players, X and O, take turns placing their mark in a gird. The first player to get three marks in a row, column, or diagonal wins the game. The game can also end in a draw, known as a “cat’s game”. An example of a Tic Tac Toe game is shown in Figure 2.1.

An example Tic Tac Toe game

Figure 2.1 An example game of Tic Tac Toe where player X is victorious.

2.2.1. Pencil and Paper

Traditionally Tic Tac Toe is played by two players using pencil and paper. This is a quick and convenient way to play with a friend. However, this does not allow for single player games. For people stuck on an airplane this can lead to extreme boredom!

2.2.2. Computer Games

Tic Tac Toe computer games allow for single player versions of the game. There are many versions of the game created over the years. Figure 2.2 shows a screen shot from one of the classic Tic Tac Toe games.

Screen shot of a Tic Tac Toe computer game.

Figure 2.2 Screen shot of Tic Tac Toe developed by James Richey.

These games can be developed as stand alone applications or can be created with the help of supporting libraries.

2.2.3. Supporting Libraries

To support the creation of Tic Tac Toe games many libraries have been developed to provide common functionality. Searching Rust’s package registry, https://crates.io/, reveals several such libraries including ultimate-ttt, zero_sum, and minimax.

With the wide variety of libraries available, for both Rust and other languages, there is likely one that meets the needs of Tic Tac Toe application developers. However, due to the Learn About Rust objective, it is worth going through the effort to create another Tic Tac Toe library.