The teacher asked about the origin of Sudoku.

Sudoku, formerly known as Jiugongge, originated in China. Thousands of years ago, our ancestors invented Luo Shu, which is more complicated than Sudoku now. It requires that the sum of the numbers in the vertical and horizontal directions is equal to 15, rather than a simple number of nine that cannot be repeated. Nine palace map in China's ancient book The Book of Changes also originated from this, so it was called "Luo Shu Nine palace map". Because of its important position in the history of China's cultural development, the name of "Nine Palaces" has been preserved to this day. 1783, the then Swiss mathematician leonhard euler invented a game called "Latin Square". This game is an n×n number square, and each row and column consists of N non-repeating numbers or letters. From 65438 to 1970s, an American magazine of mathematical logic games, Dell Puzzle Mαgαzines, began to publish the game now called Sudoku. At that time, people called it "number position". At this time, the 9×9 8 1 grid number game began to take shape. After the completion of the filling,1April, 984, Sudoku appeared in the Japanese game magazine "nikoil" ("パズルニコリ"), Wayne Gould forward the concept of "independent number", which means "this". He first published this article in The Times of England, and soon it was published in other newspapers, which soon became popular all over England. After that, it took him six years to write a computer program and put it on the website, which made the game popular all over the world. Since then, this game has swept the world. Later, due to the popularity of Sudoku, many similar mathematical puzzles were derived, such as sum of numbers and killer Sudoku. Chinese mainland officially introduced Sudoku on February 28th, 2007. On February 28th, 2007, Beijing Evening News Sudoku Federation held a certificate issuing ceremony for joining the World Puzzle Federation in the news building. At the meeting, Peter Rimiste, Secretary-General of the Puzzle Solving Federation, and the president of the club signed the certificate, which marked that the Beijing Evening News Intellectual Leisure Club became one of the 39 members of the World Puzzle Solving Federation, and also marked that the club entered the international stage, and it will dedicate it to the world.