Project 3: Ants Vs. SomeBees

Ants vs. Somebees

The bees are coming!
Create a better soldier
With inherit-ants.


Important submission note: For full credit,

  • Submit with Phases 1 & 2 complete by Thursday, July 19 (worth 1 pt).
  • Submit with Phases 3 & 4 complete by Wednesday, July 25.

You may work with one other partner for the entire project. You will get an extra credit point for submitting the entire project by Tuesday, July 24.

In this project, you will create a tower defense game called Ants Vs. SomeBees. As the ant queen, you populate your colony with the bravest ants you can muster. Your ants must protect their queen from the evil bees that invade your territory. Irritate the bees enough by throwing leaves at them, and they will be vanquished. Fail to pester the airborne intruders adequately, and your queen will succumb to the bees' wrath. This game is inspired by PopCap Games' Plants Vs. Zombies.

This project combines functional and object-oriented programming paradigms, focusing on the material from Chapter 2.5 of Composing Programs. The project also involves understanding, extending, and testing a large program.

Download starter files

The archive contains several files, but all of your changes will be made to

  • The game logic of Ants Vs. SomeBees
  • The original GUI for Ants Vs. SomeBees
  • An new GUI for Ants Vs. SomeBees
  • Utilities for displaying simple two-dimensional animations
  • Abstraction for gamestate for
  • Some functions to facilitate the game interface
  • Utility functions for CS 61A
  • assets: A directory of images and files used by
  • img: A directory of images used by
  • ok: The autograder
  • proj3.ok: The ok configuration file
  • tests: A directory of tests used by ok
  • mytests.rst: A space for you to add your custom tests; see section on adding your own tests


This is a 9-day project. You may work with one other partner. You should not share your code with students who are not your partner or copy from anyone else's solutions. In the end, you will submit one project for both partners.

Remember that you can earn an additional bonus point by submitting the project at least 24 hours before the deadline.

The project is worth 27 points. 24 points are assigned for correctness, 1 point for submitting Phases 1-2 by the checkpoint date, and 2 points for the overall composition.

You will turn in the following files:

  • mytests.rst (ungraded)

You do not need to modify or turn in any other files to complete the project. To submit the project, run the following command:

python3 ok --submit

You will be able to view your submissions on the Ok dashboard.

For the functions that we ask you to complete, there may be some initial code that we provide. If you would rather not use that code, feel free to delete it and start from scratch. You may also add new function definitions as you see fit.

However, please do not modify any other functions. Doing so may result in your code failing our autograder tests. Also, please do not change any function signatures (names, argument order, or number of arguments).

Throughout this project, you should be testing the correctness of your code. It is good practice to test often, so that it is easy to isolate any problems. However, you should not be testing too often, to allow yourself time to think through problems.

We have provided an autograder called ok to help you with testing your code and tracking your progress. The first time you run the autograder, you will be asked to log in with your Ok account using your web browser. Please do so. Each time you run ok, it will back up your work and progress on our servers.

The primary purpose of ok is to test your implementations, but there are two things you should be aware of.

First, some of the test cases are locked. To unlock tests, run the following command from your terminal:

python3 ok -u

This command will start an interactive prompt that looks like:

Assignment: Ants Vs. SomeBees
Ok, version ...

Unlocking tests

At each "? ", type what you would expect the output to be.
Type exit() to quit

Question 0 > Suite 1 > Case 1
(cases remaining: 1)

>>> Code here

At the ?, you can type what you expect the output to be. If you are correct, then this test case will be available the next time you run the autograder.

The idea is to understand conceptually what your program should do first, before you start writing any code.

Once you have unlocked some tests and written some code, you can check the correctness of your program using the tests that you have unlocked:

python3 ok

Most of the time, you will want to focus on a particular question. Use the -q option as directed in the problems below.

We recommend that you submit after you finish each problem. Only your last submission will be graded. It is also useful for us to have more backups of your code in case you run into a submission issue.

The tests folder is used to store autograder tests, so do not modify it. You may lose all your unlocking progress if you do. If you need to get a fresh copy, you can download the zip archive and copy it over, but you will need to start unlocking from scratch.

If you do not want us to record a backup of your work or information about your progress, use the --local option when invoking ok. With this option, no information will be sent to our course servers.

The Game

A game of Ants Vs. SomeBees consists of a series of turns. In each turn, new bees may enter the ant colony. Then, new ants are placed to defend their colony. Finally, all insects (ants, then bees) take individual actions. Bees either try to move toward the end of the tunnel or sting ants in their way. Ants perform a different action depending on their type, such as collecting more food, or throwing leaves at the bees. The game ends either when a bee reaches the ant queen (you lose), or the entire bee fleet has been vanquished (you win).

Core concepts

The Colony. This is where the game takes place. The colony consists of several places that are chained together to form a tunnel where bees can travel through. The colony has some quantity of food that can be expended to deploy ant troops.

Places. A place links to another place to form a tunnel. The player can place a single ant into each place. However, there can be many bees in a single place.

The Hive. This is the place where bees originate. Bees exit the hive to enter the ant colony.

Ants. Ants are the usable troops in the game that the player places into the colony. Each type of ant takes a different action and requires a different amount of food to place. The two most basic ant types are the HarvesterAnt, which adds one food to the colony during each turn, and the ThrowerAnt, which throws a leaf at a bee each turn. You will be implementing many more.

Bees. Bees are the antagonistic troops in the game that the player must defend the colony from. Each turn, a bee either advances to the next place in the tunnel if no ant is in its way, or it stings the ant in its way. Bees win when at least one bee reaches the end of a tunnel.

Queen Ant: There is one queen ant in the whole colony. She is able to attack bees but she also has a special ability of fortifying the other ant troops. Bees can also win if they destroy the queen ant.

Core classes

The concepts described above each have a corresponding class that encapsulates the logic for that concept. Here is a summary of the main classes involved in this game:

  • AntColony: Represents the colony and some state information about the game, including how much food is available, how much time has elapsed, where the QueenAnt resides, and all the Places in the game.
  • Place: Represents a single place that holds insects. At most one Ant can be in a single place, but there can be many Bees. Place objects have an exit and an entrance which are also places. Bees travel through a tunnel by moving to a Place's exit.
  • Hive: Represents the place where Bees start out.
  • Insect: A superclass for Ant and Bee. All insects have an armor attribute, their remaining health, and a place attribute, the Place where they are currently located. Each turn, every active Insect in the game performs its action.
  • Ant: Represents ants. Each Ant subclass has special attributes or a special action that distinguish it from other Ant types. For example, a HarvesterAnt gets food for the colony and a ThrowerAnt attacks Bees. Each ant type also has a food_cost attribute that indicates how much it costs to deploy one unit of that type of ant.
  • Bee: Represents bees. Each turn, a bee either moves to the exit of its current Place if no ant blocks its path, or stings an ant that blocks its path.

Game Layout

Below is a visualization of an AntColony. As you work through the unlocking tests and problems, we recommend drawing out similar diagrams to help your understanding.

Playing the game

The game can be run in two modes: as a text-based game or using a graphical user interface (GUI). The game logic is the same in either case, but the GUI enforces a turn time limit that makes playing the game more exciting. The text-based interface is provided for debugging and development.

The files are separated according to these two modes. knows nothing of graphics or turn time limits.

To start a text-based game, run


To start a graphical game, run


To start an older version of the graphics, run


When you start the graphical version, a new browser window should appear. In the starter implementation, you have unlimited food and your ants can only throw leaves at bees in their current Place. Try playing the game anyway! You'll need to place a lot of ThrowerAnts (the second type) in order to keep the bees from reaching your queen.

The game has several options that you will use throughout the project, which you can view with python3 --help.

usage: [-h] [-d DIFFICULTY] [-w] [--food FOOD]

Play Ants vs. SomeBees

optional arguments:
  -h, --help     show this help message and exit
  -d DIFFICULTY  sets difficulty of game (test/easy/medium/hard/extra-hard)
  -w, --water    loads a full layout with water
  --food FOOD    number of food to start with when testing

Your own test cases

Adding your own tests is entirely optional; you will not lose points if you submit an empty mytests.rst file.

We highly recommend that you add your own tests as you work through the project. It's a really helpful way to speed up the debugging process and improve your understanding of the code.

The course staff has also made an instructional video summarizing the information below.

Adding tests

Custom Test Example

Adding tests is easy. Directly edit the mytests.rst file included with the Ants project. We provide a sample structure to start from, but the test format is actually quite flexible. Here are some simple rules to follow:

  • Follow standard Python doctest format. This is what we mostly use for the Ok tests, so feel free to use those as examples.
  • For the most part, you may use whitespace as you'd like, but we recommend keeping it organized for your own sake.
  • Generally, smaller, simpler tests will be more useful than larger, more complex tests.

You may also find our debugging guide helpful. If you're stuck on a particularly tricky Ok test case, a good first step would be to break it up into small parts and test them out yourself in mytests.rst.

Running tests

To run all your tests in mytests.rst with verbose results:

python3 ok -t -v

If you put your tests in a different file or split your tests up into multiple files:

python3 ok -t your_new_filename.rst

To run just the tests from suite 1 case 1 in mytests.rst:

python3 ok -t --suite 1 --case 1

You might have noticed that there's a "test coverage" percentage for your tests (note that coverage statistics are only returned when running all tests). This is a measure of your test's code coverage. If you're interested, you can find more information in our reference guide.

Phase 1: Basic gameplay

Important submission note: For full credit,

  • Submit with Phases 1-2 complete by Thursday, July 19 (worth 1 pt).

In the first phase you will complete the implementation that will allow for basic gameplay with the two basic Ants: the HarvesterAnt and the ThrowerAnt.

Problem 0 (0 pt)

Answer the following questions with your partner after you have read the entire file. If you cannot answer these questions, read the file again, consult the core concepts/classes sections above, or ask a question in the Question 0 thread on Piazza.

  1. What is the significance of an insect's armor attribute? Does this value change? If so, how?
  2. What are all of the attributes of the Ant class?
  3. Is the armor attribute of the Ant class an instance attribute or class attribute? Why?
  4. Is the damage attribute of an Ant subclass (such as ThrowerAnt) an instance attribute or class attribute? Why?
  5. Which class do both Ant and Bee inherit from?
  6. What do instances of Ant and instances of Bee have in common?
  7. How many insects can be in a single Place at any given time (until Problem 9 is complete)?
  8. What does a Bee do during its turn?
  9. When does the game end?

You can test your understanding by running

python3 ok -q 00 -u

Problem 1 (1 pt)

First, add food costs and implement harvesters. Currently, there is no cost for deploying any type of Ant, and so there is no challenge to the game. You'll notice that Ant starts out with a base food_cost of zero. Override this value in each of the subclasses listed below with the correct costs.

Class Food Cost Armor

2 1

3 1

Now that deploying Ants cost food, we need to be able gather more food! To fix this issue, implement the HarvesterAnt class. A HarvesterAnt is a type of Ant that adds one food to the total as its action.

Before writing any code, test your understanding of the problem:

python3 ok -q 01 -u

After writing code, test your implementation:

python3 ok -q 01

Try playing the game by running python3 Once you have placed a HarvesterAnt, you should accumulate food each turn. You can also place ThrowerAnts, but you'll see that they can only attack bees that are in their Place, so it'll be a little difficult to win.

Problem 2 (2 pt)

Complete the Place constructor by adding code that tracks entrances. Right now, a Place keeps track only of its exit. We would like a Place to keep track of its entrance as well. A Place needs to track only one entrance. Tracking entrances will be useful when an Ant needs to see what Bees are in front of it in the tunnel.

However, simply passing an entrance to a Place constructor will be problematic; we would need to have both the exit and the entrance before creating a Place! (It's a chicken or the egg problem.) To get around this problem, we will keep track of entrances in the following way instead. The Place constructor should specify that:

  • A newly created Place always starts with its entrance as None.
  • If the Place has an exit, then the exit's entrance is set to that Place.

Hint: Remember that when inside the definition of an __init__ method, the name self is bound to the newly created object.

Hint: Try drawing out two Places next to each other if things get confusing. In the GUI, a place's entrance is to its right while the exit is to its left.

Before writing any code, test your understanding of the problem:

python3 ok -q 02 -u

After writing code, test your implementation:

python3 ok -q 02

Problem 3 (1 pt)

In order for a ThrowerAnt to attack, it must know which bee it should hit. The provided implementation of the nearest_bee method in the ThrowerAnt class only allows them to hit bees in the same Place. Your job is to fix it so that a ThrowerAnt will throw_at the nearest bee in front of it that is not still in the Hive.

The nearest_bee method returns a random Bee from the nearest place that contains bees. Places are inspected in order by following their entrance attributes.

  • Start from the current Place of the ThrowerAnt.
  • For each place, return a random bee if there is any, or consider the next place that is stored as the current place's entrance.
  • If there is no bee to attack, return None.

Hint: The random_or_none function provided in returns a random element of a sequence or None if the sequence is empty.

Before writing any code, test your understanding of the problem:

python3 ok -q 03 -u

Hint: Having trouble visualizing the test cases? Try drawing them out on paper! The example diagram provided in Game Layout shows the first test case for this problem.

After writing code, test your implementation:

python3 ok -q 03

After implementing nearest_bee, a ThrowerAnt should be able to throw_at a Bee in front of it that is not still in the Hive. Make sure that your ants do the right thing! To start a game with ten food (for easy testing):

python3 --food 10

Phase 2: Ants Attack

Now that you've implemented basic gameplay with two types of Ants, let's add some flavor to the ways ants can attack bees. In this phase, you'll be implementing several different Ants with different offensive capabilities.

After you implement each Ant subclass in this section, you'll need to set its implemented attribute to True so that that type of ant will show up in the GUI. Feel free to try out the game with each new ant to test the functionality!

With your Phase 2 ants, try python3 -d easy to play against a full swarm of bees in a multi-tunnel layout and try -d normal, -d hard, or -d extra-hard if you want a real challenge! If the bees are too numerous to vanquish, you might need to create some new ants.

Problem 4 (2 pt)

The ThrowerAnt is a great offensive unit, but it'd be nice to have a cheaper unit that can throw. Implement two subclasses of ThrowerAnt that are less costly but have constraints on the distance they can throw:

  • The LongThrower can only throw_at a Bee that is found after following at least 5 entrance transitions. It cannot hit Bees that are in the same Place as it or the first 4 Places in front of it. If there are two Bees, one too close to the LongThrower and the other within its range, the LongThrower should throw past the closer Bee, instead targeting the farther one, which is within its range.
  • The ShortThrower can only throw_at a Bee that is found after following at most 3 entrance transitions. It cannot throw at any ants further than 3 Places in front of it.

Neither of these specialized throwers can throw_at a Bee that is exactly 4 Places away. Placing a single one of these (and no other ants) should never win a default game.

Class Food Cost Armor

2 1

2 1

A good way to approach the implementation to ShortThrower and LongThrower is to have it inherit the nearest_bee method from the base ThrowerAnt class. The logic of choosing which bee a thrower ant will attack is essentially the same, except the ShortThrower and LongThrower ants have maximum and minimum ranges, respectively.

To implement these behaviors, you may need to modify the nearest_bee method to reference min_range and max_range attributes, and only return a bee that is in range.

The original ThrowerAnt has no minimum or maximum range, so make sure that its min_range and max_range attributes should reflect that. Then, implement the subclasses LongThrower and ShortThrower with appropriately constrained ranges and correct food costs.

Hint: float('inf') returns an infinite positive value represented as a float that can be compared with other numbers.

Don't forget to set the implemented class attribute of LongThrower and ShortThrower to True.

Before writing any code, test your understanding of the problem:

python3 ok -q 04 -u

After writing code, test your implementation:

python3 ok -q 04

Problem 5 (2 pt)

Implement the FireAnt, which damages all the bees in the same place as itself when it dies. To implement this, we have to override the FireAnt's reduce_armor method. Normally, Insect.reduce_armor will decrement the insect's armor by the given amount and remove the insect from its place if armor reaches zero or lower. However, if a FireAnt's armor reaches zero or lower, it will reduce the armor of all Bees in its place by its damage attribute (defaults to 3) before being removed from its place.

Class Food Cost Armor

5 1

Hint: To damage a Bee, call the reduce_armor method inherited from Insect.

Hint: Damaging a bee may cause it to be removed from its place. If you iterate over a list, but change the contents of that list at the same time, you may not visit all the elements. This can be prevented by making a copy of the list. You can either use a list slice, or use the built-in list function.

 >>> lst = [1,2,3,4]
 >>> lst[:]
 [1, 2, 3, 4]
 >>> list(lst)
 [1, 2, 3, 4]
 >>> lst[:] is not lst and list(lst) is not lst

Once you've finished implementing the FireAnt, give it a class attribute implemented with the value True.

Before writing any code, test your understanding of the problem:

python3 ok -q 05 -u

After writing code, test your implementation:

python3 ok -q 05

You can also test your program by playing a game or two! A FireAnt should destroy all co-located Bees when it is stung. To start a game with ten food (for easy testing):

python3 --food 10

Problem 6 (2 pt)

Implement the HungryAnt, which will select a random Bee from its place and eat it whole. After eating a Bee, it must spend 3 turns digesting before eating again. If there is no bee available to eat, it will do nothing.

Class Food Cost Armor

4 1

Give HungryAnt a time_to_digest class attribute that holds the number of turns that it takes a HungryAnt to digest (default to 3). Also, give each HungryAnt an instance attribute digesting that counts the number of turns it has left to digest (default is 0, since it hasn't eaten anything at the beginning).

Implement the action method of the HungryAnt to check if it's digesting; if so, decrement its digesting counter. Otherwise, eat a random Bee in its place by reducing the Bee's armor to 0 and restart the digesting timer.

Before writing any code, test your understanding of the problem:

python3 ok -q 06 -u

After writing code, test your implementation:

python3 ok -q 06

Problem 7 (2 pt)

Implement the NinjaAnt, which damages all Bees that pass by, but can never be stung.

Class Food Cost Armor

5 1

A NinjaAnt does not block the path of a Bee that flies by. To implement this behavior, first modify the Ant class to include a new class attribute blocks_path that is True by default. Set the value of blocks_path to False in the NinjaAnt class.

Second, modify the Bee's method blocked to return False if either there is no Ant in the Bee's place or if there is an Ant, but its blocks_path attribute is False. Now Bees will just fly past NinjaAnts.

Finally, we want to make the NinjaAnt damage all Bees that fly past. Implement the action method in NinjaAnt to reduce the armor of all Bees in the same place as the NinjaAnt by its damage attribute. Similar to the FireAnt, you must iterate over a list of bees that may change.

Before writing any code, test your understanding of the problem:

python3 ok -q 07 -u

Hint: Having trouble visualizing the test cases? Try drawing them out on paper! See the example in Game Layout for help.

After writing code, test your implementation:

python3 ok -q 07

For a challenge, try to win a game using only HarvesterAnt and NinjaAnt.

Phase 3: But They Also Protect

Important submission note: For full credit,

  • Submit with Phases 3-4 complete by Wednesday, July 25.

You will get an extra credit point for submitting the entire project by Tuesday, July 24.

We now have some great offensive troops to help vanquish the bees, but let's make sure we're also keeping our defensive efforts up. In this phase you will implement ants that have special defensive capabilities such as increased armor and the ability to protect other ants.

Problem 8 (1 pt)

We are going to add some protection to our glorious AntColony by implementing the WallAnt, which is an ant that does nothing each turn. A WallAnt is useful because it has a large armor value.

Class Food Cost Armor

4 4

Unlike with previous ants, we have not provided you with a class header. Implement the WallAnt class from scratch. Give it a class attribute name with the value 'Wall' (so that the graphics work) and a class attribute implemented with the value True (so that you can use it in a game).

Before writing any code, test your understanding of the problem:

python3 ok -q 08 -u

After writing code, test your implementation:

python3 ok -q 08

Problem 9 (4 pt)

Right now, our ants are quite frail. We'd like to provide a way to help them last longer against the onslaught of the bees. Enter the BodyguardAnt.

Class Food Cost Armor

4 2

A BodyguardAnt differs from a normal ant because it is a container; it can contain another ant and protect it, all in one Place. When a Bee stings the ant in a Place where one ant contains another, only the container is damaged. The ant inside the container can still perform its original action. If the container perishes, the contained ant still remains in the place (and can then be damaged).

Each BodyguardAnt has an instance attribute contained_ant that stores the ant it contains. It initially starts off as None, to indicate that no ant is being protected. Implement the contain_ant method so that it sets the bodyguard's contained_ant instance attribute to the passed in ant argument. Also implement the BodyguardAnt's action method to perform its contained_ant's action if it is currently containing an ant.

In addition, you will need to make the following modifications throughout your program so that a container and its contained ant can both occupy a place at the same time (a maximum of two ants per place), but only if exactly one is a container:

  1. Add an Ant.is_container class attribute that indicates whether a subclass of Ant is a container. For all Ant instances, except for BodyguardAnt instances, is_container should be False. The BodyguardAnt.is_container attribute should be True.
  2. Implement the method Ant.can_contain which takes an other ant as an argument and returns True if:

    • This ant is a container.
    • This ant does not already contain another ant.
    • The other ant is not a container.
  3. Modify Place.add_insect to allow a container and a non-container ant to occupy the same place according to the following rules:

    • If the ant currently occupying a Place can contain the insect (an Ant) passed to add_insect, then it does.
    • If the insect (an Ant) passed to add_insect can contain the ant currently occupying a Place, then it does. Also, set the Place's ant to be the container insect.
    • If neither Ant can contain the other, raise the same AssertionError as before (the one already present in the starter code).

Before writing any code, test your understanding of the problem:

python3 ok -q 09 -u

After writing code, test your implementation:

python3 ok -q 09

Problem 10 (1 pt)

The BodyguardAnt provides great defense, but they say the best defense is a good offense. The TankAnt is a container that protects an ant in its place and also deals 1 damage to all bees in its place each turn.

Class Food Cost Armor

6 2

You should not need to modify any code outside of the TankAnt class. If you find yourself needing to make changes elsewhere, look for a way to write your code for the previous question such that it applies not just to BodyguardAnt and TankAnt objects, but to container ants in general.

Before writing any code, test your understanding of the problem:

python3 ok -q 10 -u

After writing code, test your implementation:

python3 ok -q 10

Phase 4: Water and Might

In the final phase, you're going to add one last kick to the game by introducing a new type of place and new ants that are able to occupy this place. One of these ants is the most important ant of them all: the queen of the colony.

Problem 11 (1 pt)

Let's add water to the colony! Currently there are only two types of places, the Hive and a basic Place. To make things more interesting, we're going to create a new type of Place called Water.

Only an ant that is watersafe can be deployed to a Water place. In order to determine whether an Insect is watersafe, add a new attribute to the Insect class named is_watersafe that is False by default. Since bees can fly, make their is_watersafe attribute True, overriding the default.

Now, implement the add_insect method for Water. First, add the insect to the place regardless of whether it is watersafe. Then, if the insect is not watersafe, reduce the insect's armor to 0. Do not repeat code from elsewhere in the program. Instead, use methods that have already been defined.

Before writing any code, test your understanding of the problem:

python3 ok -q 11 -u

After writing code, test your implementation:

python3 ok -q 11

Once you've finished this problem, play a game that includes water. To access the wet_layout which includes water, add the --water option (or -w for short) when you start the game.

python3 --water

Problem 12 (1 pt)

Currently there are no ants that can be placed on Water. Implement the ScubaThrower, which is a subclass of ThrowerAnt that is more costly and watersafe, but otherwise identical to its base class. A ScubaThrower should not lose its armor when placed in Water.

Class Food Cost Armor

6 1

We have not provided you with a class header. Implement the ScubaThrower class from scratch. Give it a class attribute name with the value 'Scuba' (so that the graphics work) and remember to set the class attribute implemented with the value True (so that you can use it in a game).

Before writing any code, test your understanding of the problem:

python3 ok -q 12 -u

After writing code, test your implementation:

python3 ok -q 12

Problem 13 (4 pt)

Finally, implement the QueenAnt. The queen is a waterproof ScubaThrower that inspires her fellow ants through her bravery. The QueenAnt doubles the damage of all the ants behind her each time she performs an action. Once an ant's damage has been doubled, it is not doubled again for subsequent turns.

Class Food Cost Armor

7 1

However, with great power comes great responsibility. The QueenAnt is governed by three special rules:

  1. If the queen ever has its armor reduced to 0, the bees win. The bees also still win if any bee reaches the end of a tunnel. You can call bees_win() to signal to the simulator that the game is over.
  2. There can be only one true queen. Any queen instantiated beyond the first one is an impostor, and should have its armor reduced to 0 upon taking its first action, without doubling any ant's damage or throwing anything. If an impostor dies, the game should still continue as normal.
  3. The true (first) queen cannot be removed. Attempts to remove the queen should have no effect (but should not cause an error). You will need to modify the remove_insect method of Place to enforce this condition.

Some hints:

  • All instances of the same class share the same class attributes. How can you use this information to tell whether a QueenAnt instance is the true QueenAnt?
  • You can find each Place in a tunnel behind the QueenAnt by starting at the ant's place.exit and then repeatedly following its exit. The exit of a Place at the end of a tunnel is None.
  • To avoid doubling an ant's damage twice, keep track of all the ants who have been buffed in a way that persists across calls to QueenAnt.action.
  • When buffing the ants' damage, keep in mind that there can be more than one ant in one place!
  • You may find the isinstance function useful for checking if an object is an instance of a given class. For example:

    >>> a = Foo()
    >>> isinstance(a, Foo)

Before writing any code, test your understanding of the problem:

python3 ok -q 13 -u

After writing code, test your implementation:

python3 ok -q 13

Extra Credit (2 pt)

During Office Hours and Project Parties, the staff will prioritize helping students with required questions. We will not be offering help with this question unless the queue is empty.

Implement two final thrower ants that do zero damage, but instead produce a temporary "effect" on the action method of a Bee instance that they throw_at. This effect is an alternative action that lasts for a certain number of .action(colony) calls, after which the Bee's action reverts to its original behavior.

We will be implementing two new ants that subclass ThrowerAnt.

  • SlowThrower throws sticky syrup at a bee, applying a slow effect for 3 turns.
  • ScaryThrower intimidates a nearby bee, causing it to back away instead of advancing. (If the bee is already right next to the Hive and cannot go back further, it should not move.) The scare effect lasts for 2 turns. Once a bee has been scared once, it can't be scared again.
Class Food Cost Armor

4 1

6 1

In order to complete the implementations of these two ants, you will need to set their class attributes appropriately and implement the following three functions:

  1. make_slow is an effect that takes an action method and a bee, and returns a new action method that performs the original action on turns where colony.time is even and does nothing on other turns.
  2. make_scare is an effect that takes an action method and a bee, and returns a new action method that makes the bee go backwards.
  3. apply_effect takes an effect (either make_slow or make_scare), a Bee, and a duration. It uses the effect on the Bee's .action method to produce a new action method, and then arranges to have the new method become the bee's action method for the next duration times that .action is called, after which the previous .action method is restored.

    Hint: to make a bee go backwards, consider adding an instance variable indicating its current direction. Where should you change the bee's direction? Once the direction is known, how can you modify the action method of Bee to move appropriately?

    Hint: To prevent the same bee from being scared twice, you will also need to add an instance variable to Bee and set it appropriately!

You can run some provided tests, but they are not exhaustive:

python3 ok -q EC -u
python3 ok -q EC

Make sure to test your code! Your code should be able to apply multiple effects on a target; each new effect applies to the current (possibly affected) action method of the bee.

Optional Problem (0 pt)

During Office Hours and Project Parties, the staff will prioritize helping students with required questions. We will not be offering help with this question unless the queue is empty.

We've been developing this ant for a long time in secret. It's so dangerous that we had to lock it in the super hidden CS61A underground vault, but we finally think it's ready to go out on the field. In this problem, you'll be implementing the final ant -- LaserAnt, a ThrowerAnt with a twist.

Class Food Cost Armor

10 1

The LaserAnt shoots out a powerful laser, damaging all that dare to stand in its path. Both Bees and Ants, of all types, are at risk of being damaged by LaserAnt. When a LaserAnt takes its action, it will damage all Insects in its place (excluding itself, but including its container if it has one) and the Places in front of it, excluding the Hive.

But, if that were it, LaserAnt would be too powerful for us to contain. The LaserAnt has a base damage of 2. But, LaserAnt's laser comes with some quirks. It is weakened by 0.2 each place it travels away from LaserAnt's place. Additionally, LaserAnt's laser has limited battery. Each time LaserAnt actually damages an Insect its laser's total damage goes down by 0.05. If LaserAnt's damage becomes negative due to these restrictions, it simply does 0 damage instead.

In order to complete the implementation of this ultimate ant, read through the LaserAnt class, set the class attributes appropriately, and implement the following two functions:

  1. insects_in_front is an instance method, called by the action method, that takes in hive (the current Hive), and returns a dictionary where each key is an Insect and each corresponding value is the distance (in places) that that Insect is away from LaserAnt. The dictionary should include all Insects on the same place or in front of the LaserAnt, excluding LaserAnt itself.
  2. calculate_damage is an instance method that takes in distance, the the distance that an insect is away from the LaserAnt instance. It returns the damage that the LaserAnt instance should afflict based on:

    1. The distance away from the LaserAnt instance that an Insect is.
    2. The number of Insects that this LaserAnt has damaged, stored in the insects_shot instance attribute.

In addition to implementing the methods above, you may need to modify, add, or use class or instance attributes to the LaserAnt class as needed.

You can run the provided sanity test, but it is not exhaustive:

python3 ok -q OPTIONAL

Make sure to test your code!


Again, you will be turning in the following files:

  • mytests.rst (ungraded)

Please run the following command to submit the project:

python3 ok --submit

Then, go to your OK dashboard and verify that your submission was successful. You should see something like this:

You can click on the name of the assignment for more information about your submission. If you're experiencing issues with the autograder, remember that you can submit manually online.


You are now done with the project! If you haven't yet, you should try playing the game! There are two GUIs that you can use. The first is a new browser GUI that has fancy graphics and animations. The command to run it is:

python3 [-h] [-d DIFFICULTY] [-w] [--food FOOD]

The second is an older, but tried-and-true interface that we have been using over the past few years. The command to run it is:

python3 [-h] [-d DIFFICULTY] [-w] [--food FOOD]

Acknowledgments: Tom Magrino and Eric Tzeng developed this project with John DeNero. Jessica Wan contributed the original artwork. Joy Jeng and Mark Miyashita invented the queen ant. Many others have contributed to the project as well!

Colin Schoen developed the new browser GUI. The beautiful new artwork was drawn by the efforts of Alana Tran, Andrew Huang, Emilee Chen, Jessie Salas, Jingyi Li, Katherine Xu, Meena Vempaty, Michelle Chang, and Ryan Davis.