This site requires JavaScript, please enable it in your browser!
Greenfoot back

Greeps - The Greenfoot Programming Competition

Greepsshot Some images (for decoration of possible flyers, hand-outs, posters...):
For making your own maps:

Alien creatures have landed on Earth - they are the Greeps. Greeps like tomatoes. By some increadible stroke of luck, they have landed in an area where piles of tomatoes are found randomly spread out over the otherwise barren land. Help your Greeps collect as many tomatoes as possible.

This is the material for the original Greeps programming competition. The competition is explained in more detail as Interlude 2 in the book Introduction to Programming with Greenfoot.


The flyer: competition-flyer.pdf

The scenario to hand out (three maps only):

The full greeps version with all ten maps will not be published here (so that it is not available to participants of the competition). Teachers who want to run the competition can get it in the Greenroom.


Rule 1: Only change the class 'Greep'. No other classes may be modified or created.

Rule 2: No additional fields. You cannot extend the Greeps' memory. That is: You are not allowed to add fields to the class (except final fields). You can use the one byte memory that is provided.

Rule 3: You cannot move more than once per 'act' round.

Rule 4: You cannot communicate directly with other Greeps. That is: no field accesses or method calls to other Greep objects are allowed. (Greeps can communicate indirectly via the paint spots on the ground.)

Rule 5: No long vision. You are allowed to look at the world only at the immediate location of the Greep. Greeps are almost blind, and cannot look any further.

Rule 6: No creation of objects. You are not allowed to create any scenario objects (instances of user-defined classes, such as Greep or Paint). Greeps have no magic powers - they cannot create things out of nothing.

Rule 7: No teleporting. Methods from Actor that cheat normal movement (such as setLocation) may not be used.