Despite barely studying for an exam he claimed "wasn't very difficult", a 16-year-old Hong Kong student has notched up the highest mark in an international maths test, his secondary school said.
Anthony Leung sat the International General Certificate of Secondary Education (IGCSE) exams last June, when he was 15, and learned this week he had bested thousands of other students.
"It was quite a shock. I was very surprised and certainly happy," Leung told local paper The South China Morning Post.
"My parents were happy, a little surprised but, like me, they don't quite believe it," he added.
A school spokeswoman told AFP Leung had received a certificate from the Cambridge University saying he had the world's highest mark in IGCSE maths.
The test, designed for 14 to 16-year-olds and given at schools that teach an international curriculum, was divided into three papers, including one exam that had to be completed without a calculator, the report said.
The papers covered statistics, trigonometry and geometry, among other topics.
"It wasn't very difficult but certainly challenging," Leung said.
"But since that wasn't the only exam I was sitting, I didn't study much."
Leung isn't Hong Kong's only star student, as academic excellence is seen as key to getting ahead in the former British colony.
Last month, 10-year-old Hong Kong twins Estephe and Perrine Corlin scored straight "As" in the IGCSE maths papers, which is designed for students at least four years older.