Note pair Memorizer game. How to play Memorizer game:
You will be shown some balls with their faces down. The balls hide pairs of pictures, all mixed up. Your task is to
find all the pairs. Click on a ball, and a picture will appear. Then click on a second ball. Click on the balls, pair
by pair, to open the images. If you find a correct pair, the images will stay uncovered. If you miss, they will flip
back. Let's see how much time you need to open all of the pairs! The game is over when you have matched all of the
pairs and all the balls are gone. The objective is to uncover all the images with as few clicks as possible.