Q: How do we use constraint propagation to solve the naked twins problem?
A: By adding another constraint function, the naked_twins function, the Sudoku Solver has a chance to remove some possible values inside the box according to the naked twins rule. The new state of the problem may has less choices in some of its boxes, and some other contraint function, in this case, eliminate and only_choice have another chance to remove more choices inside each box, compared to the problem applied by naked_twins before.
Q: How do we use constraint propagation to solve the diagonal sudoku problem?
A: By adding the two diagonal lines as two extra unit, the existed contrain function has more unit to take care of. Each contraint function add more contraint on boxes on the diagonal lines and has a chance to remove more choices inside these boxes. These extra eliminated choices causes the contrain propagation.
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.
solutions.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
The data consists of a text file of diagonal sudokus for you to solve.