Q: How do we use constraint propagation to solve the naked twins problem?
A: First, we iterate each unit (rows, columns, diagonals, and square units) to
find if there are boxes with the same possible values. If we find these boxes,
then we eliminate these possible values from their peers within the same unit.
This naked twins strategy can be executed after we execute the elimination
strategy.
Q: How do we use constraint propagation to solve the diagonal sudoku problem?
A: First, when we execute elimination strategy, we should not only eliminate
taken values from peers in the corresponding rows, columns, and square units,
but also from diagonals if the box that we are analyzing is on the
diagonals. Similarly, when we execute naked twins strategy, we also eliminate
the possible values from peers in the corresponding rows, columns, square
units, and diagonals.
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_value
function provided in solution.py
To run the simulation, please run solution.py
Before submitting your solution to a reviewer, you are required to submit your project to Udacity's Project Assistant, which will provide some initial feedback.
The setup is simple. If you have not installed the client tool already, then you may do so with the command pip install udacity-pa
.
To submit your code to the project assistant, run udacity submit
from within the top-level directory of this project. You will be prompted for a username and password. If you login using google or facebook, visit this link for alternate login instructions.
This process will create a zipfile in your top-level directory named sudoku-.zip. This is the file that you should submit to the Udacity reviews system.