Nonogram solver

A simple code to solve nonogram puzzles like this

Getting started

Install the necessary libraries:

pip install -r requirements.txt

Try out an example puzzle:

python examples/antelope/examle.py

Example of code usage

To solve the puzzle displayed above, we need to input the numbers:

• top_nums: columns on the top organized as [[column1], [column2],...]
• side_nums: rows on the left organized as [[row1], [row2],...]:

top_nums = [
    [1,3],
    [2,2,1],
    [1,5],
    [3,2],
    [1,4],
    [1,1,3,3],
    [1,1,1,1],
    [1,2,2],
    [1,1,1,3],
    [1,1,1,3,1],
    [3,2,2],
    [5,1],
    [1,7],
    [2,4,2,1],
    [1,3]
    ]
side_nums = [
    [5],
    [1,5],
    [3,1],
    [2,2],
    [3,3],
    [5,4],
    [2,4,2],
    [1,1,2],
    [1,4,1],
    [4,7],
    [4,2,2],
    [2,2,2,1],
    [1,1,1,1],
    [1,1,1,1],
    [1,1,1]
    ]

After this, solving the puzzle is simply done with

from nonogram_solver import Nonogram
my_nonogram = Nonogram(top_nums, side_nums)

# solve the puzzle
my_nonogram.solve()

# plot the solution
my_nonogram.plot_field()

For large puzzles that can take exponentially long time to solve, a feature is implemented to skip rows that allow too many possible combinations and return to them later. For this, a parameter skip_threshold can be specified when solving the puzzle (30_000_000_000 by default):

my_nonogram.solve(skip_threshold=30_000_000_000)