CS 230 Spring 2005                                                      Assignment 5 –Looping                                               100 points

Assigned: 02/21/2005

Due: 02/28/2005 at the start of class

Pre-Lab (Do Before Lab):  Bring a new disk. Plan out tasks, objects, and events needed for program. Plan out major pseudocode

Main Assignment:

Back when IRA (Individual Retirement Accounts) were invented, banks advertised them with the slogan “Retire Rich.” Let’s do some basic prediction of how much our money will grow while we are investing in an IRA account (ignoring tax consequences for simplicity).  Write a program that, given an amount of money the investor will deposit each month, an expected rate of return on investment (annual percent), and the number of months until retirement, calculates the amount of money the investor will have at retirement.  Get from the user the amount of the monthly deposit, the expected annual return on investment, and the number of months. Display monthly balance for each month in a list box (see below). Display the balance at retirement in a label or text box (locked of course).

Provide capabilities to calculate, clear the input and output to start again, and to exit.

Hand in:

• Floppy disk with an entire folder containing all files related to the project.  Please set the name of the project to something other than the default name (WindowsApplication1, …)
• Print out of your code.

Miscellaneous:

• The expected annual rate of return on investment should be entered as a percent (no percent symbol though).
• The expected return rate is annual, but in doing your monthly calculations, you don’t get a full year’s worth of earnings in a month!  Assume months are equal length and investment return is always the expected rate to keep this simple. If any questions, please ask!!!  Your calculations need to meet the requirements of the task.
• To add items to the list box, use lstboxname.Items.Add( a string ). You can build a string out of pieces using “concatenation” . E.g.  “Month: “ & monNum.toString(“ ”) &  …
• To clear the contents of a list box, use lstboxname.Items.Clear()
• Note that we have now covered specifying how many decimal places to display – display a number appropriate for the results, with currency symbols where appropriate.
• We’re no longer going to assume that the clerk enters valid and reasonable values, so ensure that values entered are numbers and that they are in acceptable range. Let’s assume that monthly contribution should be positive and no more than $400.00, return rate needs to be between 1.0 and 15.0, and number of months needs to be from 1 to 600.
• You must turn on Option Explicit and Option Strict.
• MAKE SURE YOUR PROGRAM WORKS! (i.e. gets the correct answers). Now that our program is branching and looping, we need to try more examples to make sure they work. Think, “what different possibilities need to be checked?” For each, calculate the correct answer by hand and see if your program gets it!
• Make sure you save your work before running your program. It is possible that an “infinite loop” could have to be terminated. Usually that will be ok, but if you ever had to kill VB using the task manager you could lose unsaved work.
• Put YOUR NAME, e-mail address, date and purpose in comments at the beginning of the program.
• You MUST include comments that explain your program in order to get full credit.
• Remember to use meaningful variable names, and indent to show the structure of the program (VB usually does this correctly).
• Put your name on the form as a Label or as part of the form title.
• Try to use good user interface design.