dommayhew / nqueens

A visual solution to the nQueens problem written in Haskell.

nQueens.hs

Quick Start

Compile nQueens.hs on your machine and run the executable with two optional arguments: an integer specifying the size of board to solve for, and "simple", to use a simpler but faster image template for each board. Both are optional, but to use "simple" you must specify size first. E.g.,

./nQueens // Generates an image of the solutions to 8-queens
./nQueens 10 // Generates an image of the solutions to 10-queens
./nQueens 11 simple // Generates an image of the solutions to 11-queens using the simple image template.

Dependencies and Acknowledgements

This module uses Codec.Picture from JuicyPixels to render PNGs.

I previously made an inefficient nQueens solver thrown together from shower thoughts. I discovered a more powerful algorithm through the University of Helsinki's Haskell MOOC course (exercise set 9b). This module is based on their algorithm.

Results

/images contains the results for board sizes 1-12, using the simple template for sizes 10+. You can create these images yourself using the instructions above, but I have included them in the repo for convenience.