Grid lock Lee Sze Yong
21 August 2005
(c) 2005 Singapore Press Holdings Limited
Singaporeans are hooked on a new addiction: the Japanese puzzle Sudoku
WARNING: This puzzle will get you hooked. Its name may sound like the hideous Sadako from the hit Japanese horror movie The Ring, but Sudoku can be more terrifying than the female ghost. It sucks up your time.
The Japanese brainteaser already has thousands around the world trapped in its numbered grids, and is slowly creeping into Singapore.
Sudoku, which translates roughly as 'the number that is alone' in Japanese, consists of a grid of nine rows and nine columns.
The rule is to fill in the numbers one to nine so that each number appears just once in each column, row and three-by-three square. Each puzzle has only one solution.
Books about Sudoku are now hot sellers, says MPH Distributors, a major book distributor. Sales manager Marcus Frois declines to give exact figures but says that hundreds were sold in the last two weeks and retailers have been asking for more.
'We can't seem to have enough of the books,' he says.
Mr Kenny Chan, Kinokuniya's merchandising director, says the bookstore carries eight books about Sudoku and they are all doing very well.
Two books on Sudoku - The Times Sudoku Book 2 and The Little Book Of Sudoku - were on its top 10 non-fiction bestseller list last week.
Besides books, online and PDA versions of the Sudoku puzzle are also available for downloading.
New Zealander Wayne Gould, a retired judge who creates software for Sudoku puzzles, says between 50 and 100 Singaporeans have bought Sudoku programmes from him since he started the website www.sudoku.com this year. He sells them online at US$14.90 (S$25).
Enthusiasts can also play the puzzle for free at websudoku.com
The origins of Sudoku are unclear but it is believed the puzzle started from an 18th-century game invented by Swiss mathematician Leonhard Euler, which in turn was based on an ancient Chinese puzzle, Lo Shu.
Japanese publisher Nikoli claims it brought the puzzle to Japan in the 1980s from the United States. The puzzle became popular in Japan from 1986, after the publisher made some changes to the rules.
In 1997, Mr Gould bought a puzzle book from Tokyo and began developing software that generated new Sudoku puzzles. Last year, his collaboration with British newspaper The Times snowballed into the puzzle being published in newspapers in more than 20 countries.
The craze has not just caught on with professionals and students. Others ranging from housewives to cleaners are in its clutches too.
Madam Chang Pau Juet, 48, an office cleaner, had her first shot at a Sudoku puzzle last month when her daughter, a research consultant, recommended it to her. She says in Mandarin: 'My daughter gave me the puzzles so that I won't become senile.'
She has been hooked since, spending about two hours every day working on the puzzles which her daughter prints off the Internet. She also works on them at work during her breaks.
While she gets a kick in solving the puzzles, the frustration of not getting the answers gets on her nerves.
'Sometimes I get so fed up, I just throw the paper aside,' says Madam Chang, who adds that she was never good at maths in school. 'But I will either ask my daughter for help or work on it again a few days later.'
Associate Professor Helmer Aslaksen, a lecturer at the National University of Singapore's Mathematics department, says the appeal of the puzzle is that it has nothing to do with numbers.
He says: 'You can replace the nine numbers with letters, colours or pictures and the puzzle remains the same.
'All you need is logical reasoning, systematic thinking and a bit of algorithm.'
But the Norwegian, who has been teaching here since 1989, says people with a mathematical or computer science background will have an advantage in solving the puzzles faster.
He hopes the growing popularity of Sudoku will encourage more people to embrace maths. 'Maths is not just about passing PSLE and O levels. It is really about thinking skills,' he says.
'And through Sudoku, I think people will really appreciate that.'
What's the most difficult Sudoku puzzle you have come across? E-mail it to us at email@example.com
OTHER logic puzzles that got us hooked in the past two decades:
THIS colourful brainteaser, invented by Hungarian architect Erno Rubik as a structural problem, became a worldwide hit in the 1980s.
The puzzle became so popular that it spawned a cartoon series.
Twist and turn the cubes until all the colours on each side are the same.
For those still wrestling with their cubes, find the solutions at www.rubiks.com - though there's always the option of dismantling them.
IN THE early 1990s, the computer puzzle game Tetris had the world obsessed with multi-coloured bricks.
The deceptively simple game, which originated in Russia around 1985, comprises various shapes, each made of four squares, falling down a well.
Move or rotate the shapes so that they fit neatly on a line before they reach the bottom of the screen.
Once a line is completely filled with blocks, it disappears. If the shapes are not arranged and empty spaces appear, then the well is soon filled, thus ending the game.
When the hand-held versions descended on Singapore, people were seen playing the puzzle on buses and MRT trains, at fast-food joints and HDB void decks.
The game can be downloaded to your mobile phone or PDA from various websites, including www.alex-soft.net and www.zdnetasia.com