PlaySudoku.us
Evil · Puzzle #411
5
3
2
9
7
5
8
6
1
2
9
6
8
1
9
2
3
9
1
2
7
4
6
4
5
Techniques used
- Naked Single
- Hidden Single
- Pointing Pair
- Forcing Chains
- Naked Triple
- Naked Quad
- Box-Line Reduction
- Naked Pair
There are Sudoku variants with extra constraints: Killer Sudoku (cage sums), Diagonal Sudoku, and even 3D Sudoku.
There are Sudoku variants with extra constraints: Killer Sudoku (cage sums), Diagonal Sudoku, and even 3D Sudoku.
A Sudoku grid can be solved using only row and column logic, never needing box constraints — but it becomes exponentially harder.
A Sudoku grid can be solved using only row and column logic, never needing box constraints — but it becomes exponentially harder.