square_validation

square_validation

Square-level validation utilities for Sudoku boards.

This module provides functionality for validating individual rows of a Sudoku board. Square validation is performed by extracting a valid square from the board and delegating Sudoku rule checks to the generic array validation functions.

Functions

Name	Description
square_validation	Validate the squares of a Sudoku board.

square_validation

square_validation.square_validation(board)

Validate the squares of a Sudoku board. This function checks that each of the 9 square in the Sudoku board contains the digits 1-9 exactly once, with no duplicates.

Parameters

Name	Type	Description	Default
board	list of list of int	A 9x9 grid representing a Sudoku board. Each cell should contain an integer from 1-9.	required

Returns

Name	Type	Description
	bool	True if all 9 of the squares are valid (no duplicate digits 1-9), False otherwise.

Raises

Name	Type	Description
	ValueError	If the board is not a 9x9 grid or if any of the cells contain a value outside the range 1-9.

Examples

>>> board = [
...     [4, 3, 0, 0, 7, 0, 0, 0, 0],
...     [6, 0, 0, 1, 9, 5, 0, 0, 0],
...     [0, 9, 8, 0, 0, 0, 0, 6, 0],
...     [8, 0, 0, 0, 6, 0, 0, 0, 3],
...     [4, 0, 0, 8, 0, 3, 0, 0, 1],
...     [7, 0, 0, 0, 2, 0, 0, 0, 6],
...     [0, 6, 0, 0, 0, 0, 2, 8, 0],
...     [0, 0, 0, 4, 1, 9, 0, 0, 5],
...     [0, 0, 0, 0, 8, 0, 0, 7, 9]
... ]
>>> square_validation(board)
False
>>> board = [
...     [3, 2, 6, 9, 7, 4, 8, 1, 5],
...     [8, 1, 9, 3, 5, 6, 4, 7, 2],
...     [5, 4, 7, 2, 1, 8, 9, 6, 3],
...     [9, 5, 2, 7, 3, 1, 6, 4, 8],
...     [1, 3, 4, 6, 8, 9, 5, 2, 7],
...     [6, 7, 8, 4, 2, 5, 1, 3, 9],
...     [7, 6, 1, 8, 9, 3, 2, 5, 4],
...     [2, 9, 5, 1, 4, 7, 3, 8, 6],
...     [4, 8, 3, 5, 6, 2, 7, 9, 1]
... ]
>>> square_validation(board)
True