COMP1400

1. Make the shark chase program use a recursive method. Do this by modifying the World.chase method.
2. Create a world with two animal objects. Write a recursive method so that the animals count from 1 to 20 with one animal saying the odd numbers and the other animal the even numbers.
3. Suppose you have an array (ArrayVisualization) of 10 bugs. Write a method that swaps successive pairs of elements, i.e. the first element with the second, the third with the fourth, etc. You should use a loop and variables to do this.
4. Spend a little time filling in the Course/Lecturers CATEI surveys - you should have received an email about it.  There are probably many things that can be improved. Remember, these surveys are totally anonymous. Have no fears about stating what you think, just try to make it constructive.

1. Add a number of objects in a world and place some or all the objects in a list.  Next, write a function that counts and returns the number of objects in your list.  Use this function to make every object in the list say this number.  For example, if your list has 4 objects then all four objects should say “4″.
2. Alice is still a developing language, i.e., it still contains bugs.  One of these bugs resides in the “contains” function for lists.  When you drag a list into a boolean expression (of an If/Else or While) you will have the option of selecting the “contains” function.  This function takes two inputs, a list and an object.  It should return true if the object is in the list and false otherwise.  Most of the time, this function is incorrect - verify this for yourself.  Write and test your own Boolean function that determines whether one specific object is contained in a list of objects.
3. Start work on Assignment 3. You should have a storyboard by now. If not, develop it during this lab and show your tutor next week.

1. The following code features nested loops.  How many times is the ‘inner loop’ executed?  How long does the entire block of code take to execute?  What would happen to execution time if the duration for the revolving overall Ferris wheel is changed from 12 seconds to 15 seconds? 10 seconds?
2. Give at least one significant difference between the way a Loop statement works and the way a While statement works.
3. Exercise: Saloon Sign “An old saloon (Old West) is being converted into a tourist attraction. Use 3D text to create a neon sign to hang on the front of the balcony.  Then use a loop to make the sign blink 10 times.”
4. Exercise: Frog and Ladybug “Create a world with a frog (Animals) and a ladybug (Animals).  Write an interactive program to allow the user to drag the ladybug around the scene.  (Use a let the mouse move objects event.) As the lady bug is dragged around, make the frog chase after it by moving one hop at a time without colliding with the ladybug.  If the user moves the ladybug within 2 meters of the frog, have the frog look at the camera and say ‘ribbit’ - then end the animation.”

For the 3rd and final assignment, you will design and implement a program for managing phone contacts in Alice.

Requirements

Your program must include:

1. A means for adding a phone contact.  You can assume that a phone contact consists of two strings: aname and a number (stored as a string since you cannot have leading 0’s in a number).
2. A means for searching the number of a contact, i.e., the user enters a name and your program displays the corresponding number.
3. A means for deleting a contact when a user enters a name.

Optional pair work

For this assignment you have the option of working by yourself or with one partner. Use your imagination to make this seemingly boring application as interesting as possible, while still meeting the requirements above.

Marking

Marks are distributed as follows:

Design presentation: 20%

Your design will now need to include flowcharting to indicate the different possible directions the control flow may take. It will also include a short user manual describing what your program does and how to use it.

Implementation: 50%

Implementation marks will be based on the correctness of your code and organisation of your methods. Methods should make sense as units of code and not just be a random collection of lines.  Marks will also be awarded for virtuosity and additions you make above the basic specification.

Code readability: 30%

Readability marks are given for:

• Clear and concise commenting
• Meaningful naming of methods and objects
• Avoiding “magic numbers”