Editing 2015 Dec Silver Problem 2 High Card Wins (section)

== Problem ==

"Bessie the cow is playing a card game against her friend Elsie. Both of them are dealt a hand of N cards (2 ≤ N ≤ 50000). Since they are playing "High Card Wins", the player with the highest card in each round wins. If both players play the same card, Bessie wins.

Given the cards that Elsie will play in each round, your job is to determine a sequence of cards for Bessie to play such that she wins as many rounds as possible."