By cheryl tan

A Singaporean based in the United States has won a national Sudoku contest there, beating 68 contestants in cracking the killer Japanese number puzzles.

The local brainbox, who won top prize in the third annual Sudoku National Championship in Philadelphia last Saturday, is Tammy McLeod, a 32-year-old computer programmer with search engine giant Google.

Apart from the coveted title, she also wins US$10,000 (S$14,000), an iPod Touch and a place to represent the United States at the 2010 World Sudoku Championship to be held again in Philadelphia next April.

Mrs McLeod was formerly from Raffles Girls' School (RGS) and Raffles Junior College (RJC).

The mother of a 14-month-old baby girl, Audrey, she is also an alumni of the gifted programme in Rosyth Primary School and won the smartest Mensa competition in 1995. She has an IQ of 168.

She moved to the United States in 2000 and lives in Los Angeles with her 35-year-old husband, Mr Brent McLeod, a video games designer.

All that academic rigour from studying at RGS and RJC must have helped, judging by the way in which Mrs McLeod triumphed - she showed that slow and steady could indeed win the race.

Her time of seven minutes 41 seconds made her actually second to rival and ex- Sudoku champion Thomas Snyder's speedy time of four minutes and 14 seconds. But it was her perfect finish of the puzzle that helped her clinch top spot, as Snyder was careless and made an error by filling in two sixes in the same row.

The logic game, which is also popular here, is solved by filling numbers in squares on a grid that allows the numbers one to nine to be filled in only once in boxes within a row and column.

Still reeling from the shock of her win, Mrs McLeod said from her home in Los Angeles in a telephone interview: 'I didn't expect it to happen. I'm still not as fast as Thomas but I was more careful this year.'

Indeed, it is not the first time the computer whiz, who started her Sudoku obsession 21/2 years ago, has been in the top three.

She showed off her Sudoku logic prowess by taking second place the first time she joined the national championship when it was started three years ago.

In the second year, she was third, but with an imperfect puzzle, and said she had let herself down by making mistakes then.

This time around, she had to beat 68 other contestants in her advanced group in three elimination rounds within half an hour for each round. After that, she had to compete in age categories and by the towns across the states that contestants represented.

Happily for Mrs McLeod, husband Brent took along daughter Audrey to the event to give her support.

Wearing noise-cancelling ear protectors to help them concentrate, the finalists had to complete their puzzles onstage on big white boards in front of more than 1,000 onlookers.

Mrs McLeod's back was to the audience but the mum, who is uncomfortable in front of crowds, said: 'I had to forget about them and pretend they weren't there, otherwise I would have had stage fright.'

The national event has gained in clout as the United States' largest puzzle championship due to the hundreds of people who take part and its intense day-long timed competitions.

While Mrs McLeod makes solving advanced Sudoku puzzles look easy, it took time even for someone like her to pick up.

Choosing to start with the most difficult of puzzles, she picked up an extreme Sudoku puzzle book 21/2 years ago at an airport during a business trip and could not finish any of the puzzles in the book.

'I would sit and stare at the puzzles. It was a three-day trip and that's all I did. I would do it during lunch and in my hotel room,' said Mrs McLeod, who has bachelor's and master's degrees in electrical engineering and computer science from the Massachusetts Institute of Technology.

When she eventually did 'conquer' her first puzzle, she said it felt as if she had achieved something really big.

In Singapore, her parents are Captain Teddy Yap, 60, a senior chartering adviser in an oil firm, and Madam Lysha Woo, in her 50s, who works in an insurance company.

Madam Woo said: 'She used to enjoy jigsaw puzzles when she was younger and had an aptitude for numbers and liked computers.'

Her younger brother Marcus, 29, used to work in a bank and is currently pursuing his Bar exams. Her sister, Ashley, 15, is sitting for her O levels.

In her telephone interview, Mrs McLeod also said that the biggest draw about Sudoku was that it relies on reason and logic instead of knowledge, culture and an extensive vocabulary.

She said: 'On some days if you're tired, you lose your vocabulary ability because you can't think straight. Reason is always with me, it's always there.'

Hooked on the game, she went on to develop her own technique to solve the puzzles faster and did them everywhere, even while having lunch with her friends.

'I can solve the puzzle and speak at the same time,' she said with a laugh.

She is not about to let her lack of American citizenship hamper her chances of competing on the world stage, either.

Mrs McLeod, who is a Singaporean, plans to submit an application to convert to an American citizenship.

The competition officials are still debating on her status as she is a permanent resident in the US.

But if that fails, she said: 'There's a possibility that I might have to represent Singapore as a solo competitor as there is no Singapore team.'

tcheryl@sph.com.sg

'I had to forget about them and pretend they weren't there, otherwise I would have had stage fright'

Computer programmer Tammy McLeod (with husband Brent McLeod and daughter Audrey), on completing her puzzle onstage in front of more than 1,000 onlookers.

This article was first published in The Straits Times.