Classic sudoku in 4 difficulty levels
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Sudoku: A Globally Addictive Logic Game

Sudoku, a seemingly simple yet profoundly wise game, has captivated millions worldwide, becoming a popular choice for leisure and entertainment. But when was Sudoku invented? And who created it? Let's delve into the mysterious origins of Sudoku and explore its rules.

Sudoku's genesis can be traced back to the 18th-century Swiss mathematician Leonhard Euler. Euler's research introduced the concept of Latin squares, which are n×n grids filled with numbers from 1 to n such that each row, column, and sub-square contains unique numbers. This laid the foundation for the birth of Sudoku.

However, as a modern number-placement puzzle game, Sudoku's true origins date back to the 1880s. It was an American architect and retired teacher, Howard Garns, who created a number-placement puzzle based on Latin squares. Garns used the game in his classroom to teach students logical thinking. Unfortunately, it didn't receive much attention at that time, and the game remained relatively unknown.

It was until the 1970s when the American magazine "Dell Pencil Puzzles and Word Games" started publishing Sudoku puzzles that the game gradually caught people's attention. Then, in Japan, the game magazine "Nikoli" introduced Sudoku to the country and coined the name "Sudoku." One of Nikoli's employees, Maki Kaji, modified the game, increasing its difficulty, making it more challenging. Sudoku quickly gained popularity in Japan, evolving into a nationwide intellectual game.

The rules of Sudoku are straightforward yet require meticulous logical reasoning. The standard Sudoku grid consists of a 9×9 square divided into nine 3×3 subgrids called boxes or regions. The game starts with some of the squares already filled with numbers, and the player's task is to fill the remaining squares using numbers 1 to 9, ensuring that each row, column, and 3×3 box contains all the digits from 1 to 9 without repetition.

Solving Sudoku requires patience and attention to detail. However, the sense of accomplishment when you gradually unravel the puzzle and find the correct answers is immeasurable. Sudoku not only exercises one's logical thinking but also enhances concentration and patience. Therefore, it is an excellent tool for both children and adults to improve their cognitive abilities.

Today, Sudoku has become a global intellectual game, with countless enthusiasts challenging themselves online and offline. Its charm lies in its simplicity and challenging nature, providing a relaxing yet stimulating environment for exercising one's mind.

In conclusion, Sudoku is a game that combines entertainment and intellectual stimulation. Although its origins date back several centuries, it remains as captivating as ever. Join the millions of Sudoku enthusiasts worldwide and embark on a journey of logical thinking and fun!