Sudoku Validator
Write a function that validates a finished sudoku board. It should take a vector of vectors. The inner vectors represent rows from the sudoku board. The rows should contain nine integers. If the board is well-played, the function should return true
, otherwise, false
.
(sudoku-valid? [[ 1 5 2 4 8 9 3 7 6 ]
[ 7 3 9 2 5 6 8 4 1 ]
[ 4 6 8 3 7 1 2 9 5 ]
[ 3 8 7 1 2 4 6 5 9 ]
[ 5 9 1 7 6 3 4 2 8 ]
[ 2 4 6 8 9 5 7 1 3 ]
[ 9 1 4 6 3 7 5 8 2 ]
[ 6 2 5 9 4 8 1 3 7 ]
[ 8 7 3 5 1 2 9 6 4 ]]) ;=> true
(sudoku-valid? [[ 1 1 2 4 8 9 3 7 6 ]
[ 7 3 9 2 5 6 8 4 1 ]
[ 4 6 8 3 7 1 2 9 5 ]
[ 3 8 7 1 2 4 6 5 9 ]
[ 5 9 1 7 6 3 4 2 8 ]
[ 2 4 6 8 9 5 7 1 3 ]
[ 9 1 4 6 3 7 5 8 2 ]
[ 6 2 5 9 4 8 1 3 7 ]
[ 8 7 3 5 1 2 9 6 4 ]]) ;=> false
Notes:
- A sudoku puzzle is successfully solved if all rows contain the numbers 1-9, all columns contain 1-9, and the nine 3x3 boxes contain 1-9. See the Wikipedia page for more information.
Thanks to this site for the challenge idea where it is considered Expert level in JavaScript.
Going crazy with transducers... Not obvious, but it's the fastest I could come up with. Thanks to Steffan Westcott for the inspiration of
blocks3
, which I translated into transducers.