A set of $$40$$ playing cards have $4$ different colours. The number of cards of the $$4$$ different colours are $$4$$, $$8$$, $$12$$ and $$16$$ respectively. A card dealer then selects some cards with his eyes closed. At least how many cards must he select such that there will definitely be $$10$$ cards of the same colour? 
Overseas Competition->Knowledge Point->Combinatorics->Pigeonhole Principle