CS 1320 (Principles of Algorithm Design I):
Homework #4
- Assigned:
- February 16, 2000.
- Due:
- February 23, 2000, at midnight.
- Credit:
- 20 points (10 points per problem).
Instructions
Write a C++ program to solve each of the problems below.
Your code should begin with comments that describe
what the program is supposed to do, in terms of its inputs
and outputs.
See the sample programs
for examples.
Problems
Distance between points
Given two points in three-dimensional space, expressed in terms
of their x, y, and z coordinates, the distance between them is
defined to be the square root of the following sum:
the square of difference between their x coordinates plus
the square of difference between their y coordinates plus
the square of difference between their z coordinates.
Write a C++ program to compute distance between two
three-dimensional points. Your program must include:
- A function to compute the distance. This function
should take six input parameters, all
doubles, representing the x, y, and z coordinates
of the two points, and return a double
representing the distance between the two points.
- A main program that prompts the user for the two sets
of coordinates (x, y, and z) and computes and prints the
distance between them.
Remember to include, for each function you write,
comments describing its precondition(s) and postcondition(s).
Credit-card billing
Acme Bank has decided to offer an AcmeCard credit card
with terms as follows.
Customers who pay off their previous month's bill will not
be charged interest for the current month.
For other customers, interest due this month will be
the monthly interest rate times the "revolving balance"
(previous month's balance minus payment) plus half the
current month's charges.
The minimum payment due each month will be 5 percent of
the customer's new balance (previous balance minus payment,
plus current month's charges plus interest).
Write a C++ program that computes information for an AcmeCard bill.
Your program should read in interest rate (as an annual percentage,
e.g., "12" for 12 percent per year), previous balance, last payment, and
current month's charges. All amounts are to be entered in
floating-point form (e.g., "12.34" for $12.34). It should then
print out interest due, new balance, and minimum payment.
All amounts should be printed out in dollars-and-cents form,
e.g. "$12.34".
Here are some examples:
| Interest rate |
Previous balance |
Last payment |
Current charges |
Interest |
New balance |
Minimum payment |
| 12
|
100.00
|
100.00
|
50.00
|
$0.00
|
$50.00
|
$2.50
|
| 12
|
200.00
|
100.00
|
40.00
|
$1.20
|
$141.20
|
$7.06
|
You do not need to worry about rounding.
Use as many or as few functions as you choose.
What to turn in
Submit your source code as described in the
guidelines for programming assignments.
For this assignment:
- Use a subject header of "cs1320 homework 4".
- Submit two source files, one for each problem.
Please choose names for the two files that indicate
which program solves which problem.
(For example,
you could use distance.cc and credit_card.cc.)