Simple Sudoku Solver written in Rust

This project is a toy project that I have written to get familiar with the Rust language. It contains a simple algorithm to solve sudokus.

No demo visible here? View it on asciinema.

Getting started

Download the latest release from GitHub. Use the version that matches your operating system.

Use the --help flag to get familiar with all options.

$ rs-sudoku --help
Rust Sudoku Solver 0.3.0
dotcs <[email protected]>
Simple sudoku solver written in Rust

USAGE:
    rs-sudoku [FLAGS] [OPTIONS] <INPUT>

FLAGS:
    -h, --help             Prints help information
        --show-unsolved    Shows the unsolved sudoku next to the solution
    -V, --version          Prints version information
    -v, --verbose          Sets the level of verbosity, can be used multiple times to increase verbosity

OPTIONS:
        --algorithm <algorithm>    Selects which algorithm will be used to solve the sudoku. [default: backtracing]
                                   [possible values: backtracing, montecarlo]
        --max-tries <max-tries>    Defines the maximum number of tries to iteratively solve the sudoku. [default:
                                   100000]

ARGS:
    <INPUT>    Sets the file to read the sudoku from

In the examples folder of this respository a few Sudokus are located that can be use to quickly try out this Rust implementation. Other Sudokus can be used as well. The files should match the same format as shown in the examples.

To solve a sudoku run

$ rs-sudoku /path/to/sudoku.txt
435|269|781
682|571|493
197|834|562
-----------
826|195|347
374|682|915
951|743|628
-----------
519|326|874
248|957|136
763|418|259

To compare this with the input use the --show-unsolved flag. Add more output with the -v / --verbose flag.

$ rs-sudoku -v --show-unsolved /path/to/sudoku.txt
INFO: Using input file: /path/to/sudoku.txt
INFO: Solved. Needed 63 tries.
xxx|26x|7x1 -> 435|269|781
68x|x7x|x9x -> 682|571|493
19x|xx4|5xx -> 197|834|562
----------- -> -----------
82x|1xx|x4x -> 826|195|347
xx4|6x2|9xx -> 374|682|915
x5x|xx3|x28 -> 951|743|628
----------- -> -----------
xx9|3xx|x74 -> 519|326|874
x4x|x5x|x36 -> 248|957|136
7x3|x18|xxx -> 763|418|259

Currently two algorithms are implemented. Use the --algorithm parameter to choose between backtracing (brute-force) and montecarlo methods.

Development

Install Rustup first. Then clone this repository and run

$ cargo run -- examples/sudoku1.txt
435|269|781
682|571|493
197|834|562
-----------
826|195|347
374|682|915
951|743|628
-----------
519|326|874
248|957|136
763|418|259