Problem Statement  
Dmitry likes TopCoder Single Round Matches. Once, he registered for an SRM and was waiting for the coding phase to begin. To entertain himself while waiting, he decided to play the following game.
He makes a pile of cards, and on each card, he writes the number of an SRM in which he has competed. No two cards contain the same number. He then takes turns until the pile is empty. Each turn consists of the following sequence of actions:
You are given a int[] cards containing the numbers written on the cards in the pile before the start of the game. Return the largest possible number of turns in which Dmitry can finish the game.  
Definition  
 
Constraints  
  cards will contain between 1 and 50 elements, inclusive.  
  Each element of cards will be between 1 and 499, inclusive.  
  All elements of cards will be distinct.  
Examples  
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