This program creates a standard card deck, shuffles it using random access on an int array, then shuffles again using the "Riffle" method, where you divide the deck into two 'halves' which may be unequal in size and stack card by card from each half until you have a shuffled deck.
isSingleRiffled is a Riffle check that ensures all cards in the deck have been shuffled using the Riffle method.