Andy Cashman must be the king of speed when it comes to writing.

The 21-year-old from Stukeley Meadows created 45 original stories in just 15 hours on Sunday.

He wrote a new flash fiction story – a form that allows for tales of between 250 and 1,000 words – every 20 minutes, raising money for the Teenage Cancer Trust.

“Flash fiction is something I discovered at university,” Andy said. “I really enjoy the way short form can invoke an emotional reaction novels can struggle to attain. I want to release a collection of flash fiction and figured a writing marathon would be a good way of getting a lot of new material.

“The challenge was ok until about nine hours in and I started getting a bit of a headache and feeling ill, so I took a rest. There were tough moments but for the most part it was very enjoyable.”

The writer graduated this year from Birmingham University with a 2:1 in English with creative writing.

Andy said his challenge was inspired by poet Tim Clare, who dedicates one day a year to write 100 poems. Andy opted for flash fiction as he insists his own poems were not good enough.

He chose the Teenage Cancer Trust as the charity helped a university friend of his.

Despite the short format, Andy estimates he wrote about 13,500 words on Sunday – the same required for a short novel.

Teenage Cancer Trust fundraiser Ian Norris said: “We’ve been so impressed with Andy’s incredible enthusiasm in putting this truly original idea together and we’d like to say a huge thank you to him for using his talent in this way.”

Andy’s work will be published online at www.flashfiction fortyfive2014.blogspot.co.uk.

INFORMATION: To donate, visit www.justgiving.com/Andy-Cashmore-Teenage-Cancer-Trust.