CSC 211 Spring, 2003

Assignment 4

Writing short programs

Due: 11:59pm, Friday, May 2^nd

Purpose: This assignment asks you to write two programs.

Write a program called InvoiceSingleItem that does the following:

• It prompts the user for the quantity of an item being ordered and the unit cost of that item (in dollars).
• Next, it computes the item's extended cost, which is the quantity times the unit cost.
• It then computes the invoice net amount, which, in this case, is simply the extended cost of the one item.
• It then computes the invoice gross amount, which is the net amount plus a 5 percent tax.
• Finally, it displays the gross amount in a dialog box. 

For example, if the user enters 20 for quantity and 6.00 for unit cost, the program will compute a net invoice amount of $120.00 (which is 20 times 6.00) and a gross invoice amount of $126.00 ($120.00 plus 5 percent).  Name the file for the program InvoiceSingleItem.java. 

Write a program called InvoiceMultipleItems that does the following:

• It repeatedly prompts the user for the quantity and unit cost of one item after another.   Each time it computes that item's extended cost and adds it to a running total of extended costs.  It will continue to do this until the user enters a quantity of 0.
• Next, it should compute the net invoice amount, which is simply the running total of the extended costs.
• It then computes the invoice gross amount, which is the net amount plus a 5 percent tax.
• Finally, it should display the gross amount in a dialog box.

For example, if the user enters:

• 20 for quantity and 6.00 for unit cost;
• and then 10 for quantity and 5.00 for unit cost;
• and then 15 for quantity and 7.00 for unit cost;
• and finally 0 for quantity,

the program will compute a net invoice amount of $275.00 (120.00 + 50.00 + 105.00) and a gross invoice amount of $288.75 ($275.00 plus 5 percent).  Name the file for the program InvoiceMultipleItems.java. 

What to submit: Through COL, submit a zip file containing both the InvoiceSingleItem.java file and the InvoiceMultipleItems.java file.