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Sudoku Tutorial

Sudoku is one of the most popular number puzzles. According to recent research published in the International Journal of Geriatric Psychiatry, solving Sudoku or other number puzzles may help to improve your attention, memory, and reasoning, and may even keep your brain ten years younger.

Our tutorial provides in-depth analysis of the most useful Sudoku solving techniques that will help you to improve your solving skills. The Sudoku Solver is one of the most important parts of our tutorial. The Sudoku Solver provides step-by-step detailed solutions for almost any Sudoku puzzle. Using the Sudoku Solver can help you approach the most challenging obstacles you may find while working on your puzzles.

Below is a list of topics covered in our Sudoku Tutorial:

Introduction to Sudoku

Sudoku RulesSudoku Rules: Sudoku rules are simple: each 3x3 block, each row, and each column has to contain all the numbers from 1 to 9 and each number should only appear once in each box, row, and column. Read More
Sudoku HistorySudoku History: According to Chinese legend, the first Magic Square was discovered by the Emperor Yu the Great (c. 2123 – 2025 BC) when a magical turtle emerged from the water with the curiously unnatural Lo Shu pattern on its shell: Read More

Sudoku Algorithms

Naked SingleNaked Single: According to Sudoku rules, the number in a cell can appear only once in each block, each row, and each column. For each cell we can create a list of possible candidates that can appear in a cell. Read More
Conflicting CandidatesConflicting Candidates: A list of hints in any cell represents the variety of possible candidates for this cell. If one of the possible candidates in the cell (a hint) has the same value as any cell in the same box, row, or column, Read More
Naked PairsNaked Pairs: Naked Pairs are the two cells in the same block, row, or column which have exactly the same pair of two candidates and there are no other candidates in these two cells. Read More
Hidden SinglesHidden Singles: According to Sudoku rules, each number should appear at list once in each box, row, and column. Hidden Single is a number that appears as a possible candidate Read More
Hidden PairsHidden Pairs: Hidden Pairs are similar to the Naked Pairs. They are two cells in the same block, row, or column which have exactly the same pair of two candidates. Read More
Box/Line ReductionBox/Line Reduction: The Box/Line Reduction technique is similar to the Hidden Single. In the Hidden Single technique, we are looking for a number that appears as a possible Read More
Naked Triples and QuadsNaked Triples and Quads: Naked Triples are very similar to Naked Pairs. As the name indicates, there is a list of three candidates, and are three cells in the same block, row, or column, which have no other candidates in these three cells except those from the list. Unlike Naked Pairs, it is not required for Naked Triples that all three sells have all tree candidates, but each of selected candidates should be presented in at least one of these cells. Read More
Pointing PairsPointing Pairs: The Pointing Pairs technique helps to remove conflicting candidates in the same row or column. If a number appears as a possible candidate only in one row or column in a box, this number should not appear in the specified row or column in any other box. Read More
ChainsChains: Chains are the most complicated Sudoku solving techniques. This strategy is used when no other technique allows solving the Sudoku. A Chain is a sequence of related candidates. Making an assumption on one candidate might affect other candidates in a Chain. Read More

Sudoku Solver

ChainsHow to Use Sudoku Solver: presents a Sudoku Solver to help Sudoku players to improve their solving skills. On each click on the “Next Step” button, the help message board (area C) presents the detailed explanation of the next step. On the Sudoku grid (area A) the hints related to the next step are marked by different colors according to the solving logic. Read More

To open the Sudoku Solver, please follow the link: Sudoku Solver.
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