The present book aims to provide systematic and reliable techniques, called the global solution, for Sudoku puzzles. Any proper Sudoku puzzle, which has one and only one solution of Sudoku, can be solved by anyone following the techniques provided in this book. Specific symbols are introduced to express the 6 basic rules of the Sudoku global solution, as the results, those Sudoku solving techniques are presented similar to the annotations in chess. Finnish mathematician Arto Inkala proposed "the most difficult Sudoku puzzle" in 2007. Then, he designed another difficult Sudoku puzzle in 2012, named "the thing Everest". In the present book the solving process of those two difficult Sudoku puzzles are illustrated reliably by the specific symbols of the global solution step by step. Key Features: o This book aims to provide the systematic and reliable techniques for Sudoku puzzles. Any proper Sudoku puzzle, which has one and only one solution of Sudoku, can be solved by anyone following these techniques provided in this book, step by step o The world’s hardest Sudoku puzzle designed by the Finnish mathematician Arto Inkala, was solved by the global solution step by step in this book o It demonstrates that anyone without advanced mathematical training could learn and apply the global solution introduced in this book to solve most of the Sudoku puzzles including even extremely difficult ones

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