Because that's what he's been practicing with. CS courses in schools in Eastern Europe are tought in Pascal, or at least used to be.

In the end it's as interesting as the brand of chess pieces at a chess tournament. If you look at the solutions to Google Code Jam (http://www.go-hero.net/jam/10/languages/0) for example then you'll see that it's mostly disgusting code made of arrays and loops and you can do those in pretty much any language. People get good at algorithms by sitting down, learning and implementing them, not by sweating the choice of language.

And in answer to your question: meh, Pascal and C are pretty much the same damn language with a couple of minor changes, and C++ mostly just adds a bunch of junk which is useless for small projects.