Q: How do we use constraint propagation to solve the naked twins problem?
A: Since the naked twins method introduce a constraint that helps to reduce the possibility space of sudoku board, it has to be used in the constraint propagation chain together with the elimination and only choice strategies. I add the call of naked_twins function in reduce_puzzle function after eliminate and only_choice.
Q: How do we use constraint propagation to solve the diagonal sudoku problem?
A: We have to add two extra units given by the boxes that belong to the two diagonals and update the set of peers in such a way that the boxes that belong to the diagonals have as peers boxes in the same row, column, 3x3 box and diagonal. The constraint propagation strategy remains the same of normal sudoku.
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.