In a previous assignment, you showed a couple of graphics, where each can be moved by the arrow keys, or w/a/s/d. The idea is that two people could share a keyboard and play against each other. We will call the character controlled by the arrow keys as "player1" and the character controlled by w/a/s/d "player2".

This assignment builds on that. In this one, add collision detection. Each character should be its own sprite. First, add a third sprite as an item to collect. If the sprite controlled by one of the players collides with it, that player should get 10 points. You can display points as text above or below the canvas.

Once you have this working for one collectable sprite, create many more of them, but keep it an odd number. This way, after the players will collect all of them, one player will have a higher score. You can use the balloons.png graphics sheet for the collectable items.

Think about this: is it possible for the two players to collide with an collectable item at the same time? If so, how would you resolve it? If your game always checks player1 first, and awards the points to player1 if both players get to the item at the same time, then player1 would have a hidden advantage. (To answer this, you can add some comments to the collision function.)