Challenge Yourself

Try to solve today's puzzle without erasing any pencil marks — plan every elimination before committing.

Challenge Yourself
✓ Completed! 👍
7
3
2
1
1
6
9
7
1
3
9
6
1
8
2
9
4
9
8
3
8
4
2
4
5
Math Insight

The constraint propagation used in Sudoku solving is the same algorithm used in AI planning and automated theorem proving.

Math Insight