UAIS Fall 2022 Hex Bot Tournament

This document is close finalized and subject to change at any time

The UAIS is planning to host a hex bot tournament. We're planning a series of workshops to get your team ready to win. Dates are broadly undecided and will be announced sometime mid October. The tournament itself will likely take place at the end of fall semester or right at the beginning of winter 2023

This repository contains a reference implementation for a very basic random guess bot, the central communicating program, and defines the communication protocol. Bots must adhere to this protocol exactly, lest an inconsistent state between opponents arise. To ensure that adherence is ensured, a test script in "Test/" has been provided which takes the name of your program as an argument.

The Bot infrastructure is 🚀blazing fast⚡, since it's been written in fearlessly concurrent and zero-cost abstracted ✨Rust✨.

Board size and turn limits will depend on the number of contestants interested, and the computing power IST is willing to lend us. We're aiming to use 11x11 boards, since this data set has a lot of training examples for 11x11. We're aiming for 5 games per bot, possibly with 2 minute turns

If there's enough interest, we'd also like to do a smaller board bracket, say 7x7. This bracket may be of better interest to search algorithms and newcomers

Hex the board game

Hex is a classic board game for bots to play. It consists of two players, we'll denote them red and blue, trying to form and uninterrupted path between their sides of the board. On each turn, a player must place exactly one piece in any untaken tile. It's like extended tiktoktoe

Our board uses coordinates of the form [a-z][0-9]+. Hexagons are adjacent to 2-6 other hexagons, depending on their position. An example of our coordinate system on a 4x4 grid looks like the one below. Bots must be able to implement up to 26x26 sized boards. All boards will be square

Central program

This program will start up both bots, send and receive communication and validate moves. Provide a full path to both executables as the argument

The program implements the following commands, which it reads from stdin line by line. Errors, such as a bot failing to start up, will be output to the stderr. Everything else goes in stdout. All commands can be used via their first letter only. For example next and n map to the same command

Cmd	Effect
help	Prints a helpful ;) message
next	Messages and receives a move from the next bot
run {}	Plays the next {} turns sequentially, where {} is an integer
show	Shows the central board
showall	Shows the internal board of each bot and the central board
check	Checks if a bot has won
quit	Shuts down both bots

Communication Protocol

We'll be keeping things simple and use stdin/stdout messaging. Your bot must implement valid responses to all the messages below. Each message is terminated by a line break, notated \n on unix. An invalid response may result in an immediate loss, so don't try to cheat

Message	Example	Description
init_board {digit}	init_board 8	Tells the bot to reset the game to an empty board w/ side length "digit"
show_board	show_board	Prints the board to stdout. Used for internal testing
make_move	make_move	Asks the bot to give their move, based on the current board
seto {}	seto a1	Tells the bot about a move for the other bot
sety {}	sety a1	Tells the bot to play a move for itself
swap	swap	Uses the opening "swap" move in Hex
unset {}	unset a1	Tells the bot to set a tile as unused
check_win	check_win	Tells the bot to check if the game is over. Returns 1 if itself has won, -1 if the opponent has won, 0 if the game has not terminated. Note that draws are mathematically impossible in Hex.
quit	quit	The game is over

Example message sequence:

init_board 11
make_move
seto a1
make_move
seto f4
make_move
quit

Message from central program	Response required from bot	Example	Internal state
init_board	None	None	Reset the board and move counters
make_move	Respond with the coordinate you set your tile at	a1	Set the tile on your board too
seto {}	None	None	Set the coordinate as the opponent's tile on your board
sety {}	None	None	Set the coordinate as the your tile on your board
unset {}	None	None	Set the coordinate as an unmarked tile on your board
quit	Exit code 0	None	Run destructors and shutdown program, preferably with exit code 0

Database

Taking sides

Your bot must take in exactly 1 positional argument, either "black" or "white". These will tell your bot which side it's playing on. See the random_bot for a python3 example

The black player wins when they have an uninterrupted path from top to bottom. For example, they could have filled 1 column with their tiles. The white player wins when they have an uninterrupted path from left to right, like a row filled with their tiles