9
3
5
2
1
2
6
4
7
9
8
7
9
4
2
3
7
1
5
2
6
5
7
2
9
5
2
9
3
2
3
1
5
4
8
2
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.
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.