Sudoku.io

Sudoku (Japanese: I on complete Sudoku), the concept of "from the Latin squares", is a Swiss mathematician at the end of the eighteenth Century, the invention of oh. A jigsaw puzzle developed in the United States and developed in japan. The puzzle is squared (i.e. 3 width x 3 up) the Affirmative shape, each divided into a fine grid. In each small square, fill in 1 to 9 numbers, so that the whole nine rows of each column, each row of numbers are not repeated. Sudoku plays a simple logic, digital arrangement of ever-changing. Many educators think Sudoku is a good way to exercise your mind.
At the same time, there is a saying that Sudoku, formerly known as the "nine palaces", originated in china. Thousands of years ago, our ancestors invented the Luo book, which features Sudoku is more complex than today's requirements, longitudinal, transverse and inclined upward of three digits and is equal to 15, rather than nine numbers don't repeat. The "nine Diagrams" in Confucian classics "the book of changes" also originates from this, so it is called "Luo Shu Jiu Fang diagram"". The name of "nine palaces" is preserved and used in the history of Chinese culture because of the important role of the book of changes in the history of Chinese culture.

This is a professional Sudoku exercise software, including the following algorithms:
1) Naked Single
2) Hidden Single
3) Hidden Single
4) Naked Pair
5) Naked Triplet
6) Naked Quad
7) Hidden Pair
8) Hidden Triplet
9) Hidden Quad