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What is Sudoku?
Sudoku is a Number Puzzle that requires no mathematical knowledge. (no adding or multiplication). It is based upon Japanese style crosswords where you are required to use logic to place numbers onto a 9x9 grid.
To solve the puzzle you must make sure that every column, row and 3x3 box contains the numbers 1 through to 9. Almost all of the puzzles can be solved using logic alone and there is no need to guess. A puzzle can take from 20 minutes to 2 hours to complete depending on its level and your experience.
For a 9x9 puzzle to have precisely one solution, the initial entries need to include at least eight of the nine digits.
The smallest number of starter clues on a sudoku puzzle is 17.
Sudoku became a world hit in 2005. When measuring its popularity in enigmatic world, it is the biggest phenomenon since Rubik's Cube in the '80s.
Some people call it newspapers saver because it boosts their sales and keeps the reader audience active. Newspapers around the world embraced it immediately because people like to solve Sudoku on a daily basis, just like crosswords.
By playing it regularly you can boost your concentration and focus, prevent or ease depression, dementia and even Alzheimer's disease according to some studies.