Nina Pell says she is useless at crosswords. But that’s OK because she is very, very good at Su Doku puzzles. At the age of 18 she beat 255 competitors to win the first Times National Su Doku Championship — and a cheque for £1,000. She completed an ultra-fiendish puzzle, the most difficult set in Britain, in 13 minutes and 48 seconds.

Nina, who is studying maths at the University of Sheffield, grew up with a fascination for number puzzles. When she first saw Su Doku on the pages of The Times a year ago, she was intrigued. “I had never seen anything like it. After I tried my first Su Doku, it became a habit immediately,” she says.

Asked whether her friends and family consider her an addict, she says: “Possibly. But the puzzles do not interfere with my day at all since each takes me five to ten minutes to complete on average.”

Her competitive edge comes from playing against her brother Graham, 19, a maths student at York. “We have speed matches and sometimes I win and sometimes he does. I wouldn’t want to say who’s better . . .”

Nina, from Monmouth, Gwent, says she uses no special tricks to complete the puzzles, simply the traditional techniques of checking the grid for obvious gaps and then labelling each box with its various possible solutions.

Neither her mother, Carol, 47, an administrator, nor her father, Maurice, 52, an engineer, attempt Su Doku. “My father would rather play golf,” she says. And she cannot get her boyfriend Joel, 18, to show any interest in her hobby.

Does she believe that women are better than men at Su Doku? “I wouldn’t necessarily say that, but it does turn on its head the myth of men being more logical and adept at numbers than women.”

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