Sudoku implements the well-known number puzzle. Objective of Sudoku is to fill the empty cells with digits ranged from 1 to 9 in a valid pattern. Some cells are already holding fixed digits and cannot be edited. A valid pattern means that

• each row does not contain any duplicate of digits, and
• each column does not contain any duplicate of digits, and
• each of the nine three-times-three subgrids does not contain any duplicate of digits.

On clicking a cell on the game board without predefined fixed digit a cursor is set. Now you can select a digit ranged from 1 to 9 to fit in the cell highlighted by the cursor position. Clearing the cell is possible via the backspace button.

Smaller markers can be used to indicate remaining candidates for the cell positions.

Some hints and facts

The Sudoku generator in use here is explicitly not only supporting symmetric cell patterns that often can be found in other Sudokus.

This type of number puzzle does actually not have Asian origin. Anyway it got popular under the name Sudoku being published by a Japanese puzzle company in mid 1980s. Sudoku is an abbreviation of the Japanese Suji wa dokushin ni kagiru. This could be translated to Digits must be singletons.

Any Sudoku solution represents a form or relation towards so called Latin square in a Mathematical sense.

Copyright (c) 2016, 2023
@author Oliver Merkel, Merkel(dot) Oliver(at) web(dot) de.
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The MIT License (MIT)

Copyright (c) 2016, 2023 Oliver Merkel, Merkel(dot) Oliver(at) web(dot)de

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The basic concept of number puzzles or more general just number constellations based on Latin squares belongs to the public domain due to its age and unknown creator.

This Sudoku type of number puzzle does actually not have Asian origin. Anyway it got popular under the name Sudoku being published by a Japanese puzzle company Nikoli in mid 1980s. Sudoku is an abbreviation of the Japanese Suji wa dokushin ni kagiru. This could be translated to Digits must be singletons.

This Sudoku implementation uses unmodified independent code libraries provided by third parties. Since their licenses might vary the corresponding information is externally linked below. Thus these external links will enable you to reproduce any copyright notice, any related list of conditions, disclaimers, and especially the copyright holders and authors of the corresponding third party functionality.

jQuery: MIT jQuery UI: MIT Raphael JS: MIT