A XO (aka tic-tac-toe/noughts and crosses) library with focus on minimum memory usage without compromising performance.
Minimum memory usage is achieve using bitboard, a common data structure in chess, adapted to fit XO game.
The current sizeof XO type is 32 bit, smaller than a pointer in most machine.
use bitboard_xo::*;
use std::error::Error;
use std::io::{stdin, stdout, Write};
/// try read a u8 from console
fn read_u8() -> Result<u32, Box<dyn Error>> {
let mut user_input = String::new();
stdin().read_line(&mut user_input)?;
Ok(user_input.trim().parse()?)
}
/// prompt user for input to get xo position
fn get_xo_pos() -> XOPos {
fn try_get_xo_pos() -> Result<XOPos, Box<dyn Error>> {
// prompt user and read row from console
print!("Input row : ");
stdout().flush()?;
let row = read_u8()?;
// prompt user and read col from console
print!("Input col : ");
stdout().flush()?;
let col = read_u8()?;
// parse row, col into XOPos
Ok(XOPos::row_col(row, col)?)
};
loop {
match try_get_xo_pos() {
Ok(xo_pos) => break xo_pos,
Err(err) => println!("{}", err),
}
}
}
fn main() -> Result<(), XOError> {
// create new XO game
let mut game = XO::new();
loop {
println!("{}", game);
// get position from user's input
let input_xo_pos = get_xo_pos();
// play at that position and match the returned game state
match game.play(input_xo_pos) {
// game end
Ok(Some(game_result)) => {
println!("{}", game);
println!("game result => {:?}", game_result);
break;
}
// game continue
Ok(None) => println!("game continue..."),
// some game error occurred
Err(xo_err) => println!("Error: {}", xo_err),
}
}
Ok(())
}
License: MIT