Got, got, need... Boffin Simon has answer to sticker album puzzler.
SO you've landed Lionel Messi but you're not sure you can afford Wayne Rooney? Fear not, for Birmingham boffin Simon Whitehouse has devised a mathematical solution to all those World Cup sticker album woes.
The 46-year-old brainbox from Moseley has compiled an equation that helps kids, and in many cases adults, calculate how many stickers they need to complete their sets.
Using a formula dubbed the Coupon Collector's Problem, the Got-Got-Need machine works out how many stickers are required.
The model works regardless of how many stickers and swaps are already held by the user.
"During the last World Cup I wrote a blog about my nephew collecting Panini stickers," Simon said.
"I had the job of finding the place in the book for his stickers.
"I did a maths equation to work out how many stickers he might expect to buy to complete the chart and it's gone from there."
Simon, a maths and computer science university graduate, said he hoped his free online resource would help to raise the profile of maths.
"It's a little side-project of mine," he added.
"It puts maths on the web. "The irony is I don't really follow football.
"The World Cup is the big one when dads buy albums to relive their youth."
To acquire all 640 stickers in the Panini album, collectors can expect to shell out for 4,505 stickers, according to the Got-Got-Need method.
But with albums (including 21 stickers) costing PS1.99, and individual packets, (containing five stickers) costing 50p, schoolboys and girls might need PS450 in pocket money.
One man who can certainly afford that is public enemy number one Mario Balotelli, scorer of Italy's winner against England last Saturday.
The former Manchester City star posted a picture on Facebook of a Panini album opened on the Italy team which had been filled entirely by his own sticker.
Balotelli accompanied the self-indulgent image with his well-known quip: "Why always me?"