If this is for programming competition, this is no less of cheating than if it is a homework. The competition should evaluate your real work and skills. Why should we help you more than your competitors? This is no good.
And, after all, you and your competitors can learn existing techniques on the Web, so what's the problem?
If I was the author of the problems for the competition, I would never pose a problem like sorting. This way, some knowledge of existing technique is evaluated, not in-depth knowledge and the ability to think. It is always possible to put forward an original problem, even though they are quite difficult to invent. Instead of offering some standard problems for a competition, it's much better not conduct any competitions at all.
So, if you are going for a real
programming competition, knowledge of known algorithms won't really help. But if you find even some known algorithm by yourself, fully independently, it can greatly improve your skills and chances to win. But in this case, if we answer your question, we will fully take away that chance from you. As I don't want to take out this chance and hence hurt you, I'm not answering, sorry. Hope it can help you.