On the Subject of Suit Shuffle

At least this module doesn’t expect you to shuffle the cards yourself.

Presented is a 5×4 grid of cards. These cards have six suits: spades, hearts, clubs, diamonds, squares and triangles. There are two squares and triangles each in the deck, and four each of the other suits. There are also four more cards on the top of the module, used to keep track of rounds.

Pressing any card on the module will start the current round: the cards will flip over to show their suits, and remain flipped for 2.5 seconds before becoming hidden again. Pairs of cards will then be swapped: the number of swaps in a particular round is equal to (2 × Round Number + 1). You must now select four cards with the same suit: doing so will complete the round, but failure to follow suit will result in a strike.

When you complete a round, one of the cards on the top of the module will flip over, showing the suit you matched. All cards of that suit will stay flipped over for all following rounds.

Complete four rounds successfully to solve the module.