# NAME

Game::Sudoku - Store, validate and solve sudoku puzzles

# SYNOPSIS

```
use Game::Sudoku;
# Create an empty game
my $game = Game::Sudoku.new();
# Set some cells
$game.cell(0,0,1).cell(0,1,2);
# Test the results
$game.valid();
$game.full();
$game.complete();
# Get possible values for a cell
$game.possible(0,2);
```

# DESCRIPTION

Game::Sudoku is a simple library to store, test and attempt to solve sudoku puzzles.

Currently the libray can be used as a basis for doing puzzles and can solve a number of them. I hope to add additional functionality to it in the future.

The Game::Sudoku::Solver module includes documenation for using the solver.

# METHODS

## new( Str :code -> Game::Sudoku )

The default constructor will accept and 81 character long string comprising of combinations of 0-9. This code can be got from an existing Game::Sudoku object by calling it's .Str method.

## valid( -> Bool )

Returns True if the sudoku game is potentially valid, IE noe row, colum or square has 2 of any number. A valid puzzle may not be complete.

## full( -> Bool )

Returns True if the sudoku game has all it's cells set to a non zero value. Note that the game may not be valid.

## complete( -> Bool )

Returns True is the sudoku game is both valid and full.

## possible( Int, Int, Bool :$set -> List )

Returns the sorted Sequence of numbers that can be put in the current cell. Note this performs a simple check of the row, column and square the cell is in it does not perform more complex logical checks.

Returns an empty List if the cell already has a value set or if there are no possible values.

If the optional :set parameter is passed then returns a Set of the values instead.

## cell( Int, Int -> Int )

## cell( Int, Int, Int -> Game::Sudoku )

Getter / Setter for individual cells. The setter returns the updated game allowing for method chaining. Note that attempting to set a value defined in the constructor will not work, returning the unchanged game object.

## row( Int -> List(List) )

Returns the list of (x,y) co-ordinates in the given row.

## col( Int -> List(List) )

Returns the list of (x,y) co-ordinates in the given column.

## square( Int -> List(List) )

## square( Int, Int -> List(List) )

Returns the list of (x,y) co-ordinates in the given square of the grid. A square can either be references by a cell within it or by it's index.

```
0|1|2
-----
3|4|5
-----
6|7|8
```

## reset( Str :$code )

Resets the puzzle to the state given in the $code argument. If the previous states initial values are all contained in the new puzzle then they will not be updated. Otherwise the puzzle will be treated as a fresh one with the given state.

# AUTHOR

Simon Proctor simon.proctor@gmail.com

# COPYRIGHT AND LICENSE

Copyright 2017 Simon Proctor

This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.