Chessboard

CLI to solve combinatoric chess puzzles.

Stable release: Last release Python versions Software license Requirements freshness

Development: Unit-tests status Documentation Status Coverage Status Code Quality

Motivation

This project started its life as a coding challenge I was asked to solve while interviewing in 2015 for a software engineering position at Uber.

After the interview proccess ended, I kept toying with the code, as a playground to test some optimization strategies in Python. It is now a boilerplate that I use to:

Examples

Simple 3x3 board with 2 kings and a rook:

$ chessboard solve --length=3 --height=3 --king=2 --rook=1
<SolverContext: length=3, height=3, pieces={'rook': 1, 'king': 2, 'queen': 0, 'bishop': 0, 'knight': 0}>
Searching positions...
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└───┴───┴───┘
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├───┼───┼───┤
│   │   │   │
├───┼───┼───┤
│   │ ♜ │   │
└───┴───┴───┘
┌───┬───┬───┐
│   │ ♜ │   │
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└───┴───┴───┘
4 results found in 0.03 seconds.

Famous eight queens puzzle, without printing the solutions to speed things up:

$ chessboard solve --length=8 --height=8 --queen=8 --silent
<SolverContext: length=8, height=8, pieces={'rook': 0, 'king': 0, 'queen': 8, 'bishop': 0, 'knight': 0}>
Searching positions...
92 results found in 119.87 seconds.

Huge combinatoric problem can take some time to solve:

$ chessboard solve --length=7 --height=7 --king=2 --queen=2 --bishop=2 --knight=1 --silent
<SolverContext: length=7, height=7, pieces={'rook': 0, 'king': 2, 'queen': 2, 'bishop': 2, 'knight': 1}>
Searching positions...
3063828 results found in 9328.33 seconds.

The CLI allow the production of a profiling graph, to identify code hot spots and bottleneck:.

$ chessboard solve --length=6 --height=6 --king=2 --queen=2 --bishop=2 --knight=1 --silent --profile
<SolverContext: length=6, height=6, pieces={'rook': 0, 'king': 2, 'queen': 2, 'bishop': 2, 'knight': 1}>
Searching positions...
23752 results found in 207.25 seconds.
Execution profile saved at /home/kevin/chessboard/solver-profile.png
Solver profiling graph

Third-party

This project package’s boilerplate is sourced from the code I wrote for Scaleway’s postal-address module, which is published under a GPLv2+ License.

The CLI code is based on the one I wrote for the kdenlive-tools module, published under a BSD license.

Indices and tables