Q: How do we use constraint propagation to solve the naked twins problem?
A: Naked twins are the case where for a given set of peers(row, col, unit) there may be a case where for any two cells there can only be two options. In such cases we can eliminate these possible values from other peer. Effectively we are adding the constraining the remaining peers of a set to exclude naked twins.
Q: How do we use constraint propagation to solve the diagonal sudoku problem?
A: From the introductory lessons we develloped a solution to sudoku puzzles, the constrains we provided for the simple case were to consider acceptable values based on rows, columns and subgrids/squares. We extend this with the diagonals and apply the same rules (only choice, reduce and tree search) to include the diagonal constraints.
This project requires Python 3.
We recommend students install Anaconda, a pre-packaged Python distribution that contains all of the necessary libraries and software for this project. Please try using the environment we provided in the Anaconda lesson of the Nanodegree.
Optionally, you can also install pygame if you want to see your visualization. If you've followed our instructions for setting up our conda environment, you should be all set.
If not, please see how to download pygame here.
solution.py- You'll fill this in as part of your solution.solution_test.py- Do not modify this. You can test your solution by runningpython solution_test.py.PySudoku.py- Do not modify this. This is code for visualizing your solution.visualize.py- Do not modify this. This is code for visualizing your solution.
To visualize your solution, please only assign values to the values_dict using the assign_values function provided in solution.py