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Event Driven Programming

Car
loan

Get Make Display
input calculations results

Get
Get Get
amount duration interest Compute Compute Display Display
rate monthly 1 st month’s headings amounts
payment payment

Calculate Apply
number of payment
months formula
Figure 8.2(b): Hierarchy Chart for the Car Loan Program.

It is clear from the hierarchy chart that the top modules manipulate the
modules beneath them. While the higher-level modules control the flow of the
program, the lower-level modules do the actual work. By designing the top
modules first, specific processing decisions can be delayed.

The following program uses the future value function. With the responses shown, the program
computes the balance in a savings account when $100 is deposited for five years at 4% interest
compounded quarterly. Interest is earned four times per year at the rate of 1% per interest
period. There will be 4 * 5, or 20, interest periods.

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