Submission for Project Euler #54: Poker hands on Hacker Rank
I wanted to avoid a massive switch-style statement where I check if the hand is a pair, two-pair, 3-of-a-kind, full house, etc etc.
So, evalHand takes a hand array as an argument (e.g. ['TH', 'TC', '6S', '7S', 'KD']) and returns an object containing the frequency of each card in the hand (e.g. {cardCount: [2, 1, 1, 1], cards: [10, 6, 7, 13]})
From this output we can quickly determine the winner by comparing the cardCount (or the cards/kicker array if the players have identical hands) for each player
Straights and flushes are special so I handled them a little differently than your normal 2-pair, three-of-a-kind, and so on