# Sudoku Solver

**URL:** <https://forum.kirupa.com/t/sudoku-solver/192582>\
**Category:** open source\
**Created:** [June 29, 2006, 3:57pm UTC](https://forum.kirupa.com/t/sudoku-solver/192582 "2006-06-29T15:57:37Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Jeff\_Wheeler](https://avatars.discourse-cdn.com/v4/letter/j/59ef9b/32.png) [@Jeff\_Wheeler](https://forum.kirupa.com/u/Jeff_Wheeler)\
**Post date:** [June 29, 2006, 3:57pm UTC](https://forum.kirupa.com/t/sudoku-solver/192582/1 "2006-06-29T15:57:37Z")

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I suppose this is as good as it’s going to get. It can solve all _hard_ Sudokus from [web sudoku](http://websudoku.com), but none of the _evil_ ones that I tried.

It’s quite OO, as there is one [font=monospace]Set[/font] class, that [font=monospace]Box[/font] and [font=monospace]Line[/font] extend from. [font=monospace]Sudoku[/font] extends from [font=monospace]Box[/font].

The [font=monospace]Set[/font] holds most methods, such as [font=monospace]getRow( _int_ )[/font] and [font=monospace]getColumn( _int_ )[/font].

Each object inheriting from [font=monospace]Set[/font] knows how to solve itself as much as possible. Also, each [font=monospace]Set[/font] has a **one-dimensional** array of [font=monospace]Cell[/font] objects. Each [font=monospace]Cell[/font] object knows its possibilities, and, once figured out, its value. They hold their possibilities in [font=monospace]Cell::value[/font]. The [font=monospace]Cell::id[/font] property is only used for cell identification and testing.

It’s important to note that you could instantiate a [font=monospace]Line[/font] object outside of the context of a Sudoku, and have it solve itself. Same goes for [font=monospace]Box[/font]es. When you instantiate any class which inherits from [font=monospace]Set[/font], the constructor will want a one-dimensional array of integers, with [font=monospace]-1[/font] or [font=monospace]null[/font] representing an unknown cell.

At any time, you can print any [font=monospace]Set[/font] class, because they all have [font=monospace]\_\_toString()[/font] methods which print them as tables. [font=monospace]Sudoku[/font] overrides [font=monospace]Set[/font]'s method, to allow several [font=monospace]Box[/font] objects to designate the borders, as would occur in a normal Sudoku puzzle.

Following are the files, in no particular order.