Description
PROGRAM DESCRIPTION:
The purpose of this programming project is to write a C++ program that uses loops and
programmer-defined functions to print out an isosceles trapezoid and calculate its area.
For reference, refer to the following diagram of an isosceles trapezoid with its formula to
compute its area:
REQUIREMENTS:
• As with all homework programs in this course, your program’s output initially
display the department and course number, your name, your SAMID, and your email address.
• You will prompt the user to enter an odd integer between 1 and 17, inclusively, to
use as the top base, b1, of the trapezoid. You will validate the user’s input by
creating a programmer-defined function to ensure that the integer is an odd
integer in the range 1 to 17, inclusively. The integer entered by the user should
be passed as a parameter to this function at a minimum (read: more parameters
may be passed as needed). If the integer is not valid, you will continually reprompt the user to enter the integer again until the user enters a valid integer.
The return type of this function should be a Boolean data type and you are to use
this Boolean result in determining whether or not the user input is valid.
• Once the user has entered a valid integer for the top base of the trapezoid, you
will then prompt the user to enter an odd integer between 3 and 19, inclusively, to
use as the bottom base, b2, of the trapezoid with the condition that the bottom
base, b2, is greater than the top base, b1. To validate the bottom base, b2, you
will use (and modify as needed) the programmer-defined function used to
validate the top base, b1, being sure to enforce the new range and the inequality
that b2 is greater than b1. Similarly, if the integer is not valid, you will continually
re-prompt the user to enter the integer again until the user enters a valid integer.
• You will prompt the user for and read in a printable character that will be used to
draw the trapezoid. You may assume that the user enters a printable character.
COSC 2347: Homework 2
2
• You will draw the trapezoid using a programmer-defined function that accepts
both integers (for each trapezoid base, b1 and b2) and the printable character
entered by the user as parameters to the function. This function should be a
void-function that does not return a value. It should print a trapezoid of the
appropriate size using the printable character entered by the user. The trapezoid
shall be drawn as follows:
o The bottom base, b2, represents the number of user-entered printable
characters used in the bottom row of the trapezoid.
o The top base, b1, represents the number of user-entered printable
characters used in the top row of the trapezoid.
o Each row shall contain two less user-entered printable characters than the
row beneath it. For example, if the bottom base, b2, is specified by 15
printable characters, then the row on top of the bottom base shall be
drawn with 13 printable characters, and so forth.
o The height of the trapezoid will be given by the number of rows it takes to
print the bottom base, b2, to the top base, b1. For example, if b2 = 13 and
b1 = 5, then this trapezoid will have a height of 5 rows (b2 = 13, next row
11, then 9, then 7, and finally b1 = 5). You may not prompt for the height of
the trapezoid.
o You may only use cout statements that print a single character (i.e., that
printable character entered by the user), a single space, or a single newline character (such as ‘\n’ or endl). The goal is to maximize the use of
repetition with nested for loops and minimize the number of cout
statements.
• After you have drawn the trapezoid, you will compute the “area” of the trapezoid
using the area formula: ���� = !
! ∗ ℎ ∗ �! + �! . You should find that this “area”
also corresponds to the number of printable characters used to print the
trapezoid itself! To compute the “area” of the trapezoid, you will create a
programmer-defined function that accepts only the two bases, b1 and b2, of the
trapezoid; thus, you must calculate the height of the trapezoid and may not
prompt the user for the height. The return type of this function should be an
integer data type and you are to use this result in printing out the value of the
area of the trapezoid.
• Your code should be well documented in terms of comments. For example, good
comments in general consist of a header (with your name, course section, date,
and brief description), comments for each variable, and commented blocks of
code.
• Your program source code should be named “homework2.cpp”, without the
quotes.
COSC 2347: Homework 2
3
• Your program will be graded based largely on whether it works correctly on the
Linux machines
• This is an individual programming assignment that must be the sole work of the
individual student.
You may assume that all input will be of the appropriate data type, although the value
itself may not be valid.
DESIGN (ALGORITHM):
On a piece of paper (or word processor), write down the algorithm, or sequence of
steps, that you will use to solve the problem. You may think of this as a “recipe” for
someone else to follow. Continue to refine your “recipe” until it is clear and
deterministically solves the problem. Be sure to include the steps for prompting for
input, performing calculations, and displaying output.
You should attempt to solve the problem by hand first (using a calculator as needed) to
work out what the answer should be for a few set of inputs. You should also use these
hand-calculations to help you figure out how to print the trapezoid (e.g., look for
relationships between the number of spaces needed versus the number of printable
characters on a row) and compute the area of the trapezoid.
Type these steps and calculations into a document (i.e., Word, text, PDF) that will be
submitted along with your source code. Note that if you do any work by hand, images
(such as pictures) may be used, but they must be clear and easily readable. This
document shall contain both the algorithm and any supporting hand-calculations you
used in verifying your results.
SAMPLE OUTPUT (input shown in bold green):
islam0299@faculty:~/cosc2347$ ./a.out
+———————————————-+
| |
|
Computer Science
COSCE 2347 – Special topic |
Student Name SamID |
+———————————————-+
Enter odd integer for base1 of trapezoid (1 – 17): 4
Enter odd integer for base1 of trapezoid (1 – 17): 19
Enter odd integer for base1 of trapezoid (1 – 17): 5
Enter odd integer for base2 > base1 of trapezoid (3 – 19): 3
Enter odd integer for base2 > base1 of trapezoid (3 – 19): 20
Enter odd integer for base2 > base1 of trapezoid (3 – 19): 18
COSC 2347: Homework 2
4
Enter odd integer for base2 > base1 of trapezoid (3 – 19): 13
Please enter a printable character to draw trapezoid: @
@@@@@
@@@@@@@
@@@@@@@@@
@@@@@@@@@@@
@@@@@@@@@@@@@
The area of the trapezoid is 45 units squared.
islam0299@faculty:~/cosc2347$ ./a.out
+———————————————-+
| |
|
Computer Science
COSCE 2347 – Special topic |
Student Name SamID |
+———————————————-+
Enter odd integer for base1 of trapezoid (1 – 17): 11
Enter odd integer for base2 > base1 of trapezoid (3 – 19): 19
Please enter a printable character to draw trapezoid: $
$$$$$$$$$$$
$$$$$$$$$$$$$
$$$$$$$$$$$$$$$
$$$$$$$$$$$$$$$$$
$$$$$$$$$$$$$$$$$$$
The area of the trapezoid is 75 units squared.
islam0299@faculty:~/cosc2347$ ./a.out
+———————————————-+
| |
|
Computer Science and Engineering
COSCE 2347 – Special topic |
Student Name SamID |
+———————————————-+
Enter odd integer for base1 of trapezoid (1 – 17): 3
Enter odd integer for base2 > base1 of trapezoid (3 – 19): 5
Please enter a printable character to draw trapezoid: &
&&&
&&&&&
The area of the trapezoid is 8 units squared.
TESTING:
Test your program to check that it operates as desired with a variety of inputs,
especially boundary values or error conditions. Then, compare the answers your code
gives with the ones you get from hand calculations.
SUBMISSION:
Your program will be graded based largely upon whether it works correctly on the CSE
machines, so you should make sure your program compiles and runs on the CSE
machines.
CSCE 1030: Homework 3
5
Your program will also be graded based upon your program style. This means that you
should use comments (as directed), meaningful variable names, and a consistent
indentation style as recommended in the textbook and in class.
• Program Header Example:
/*
============================================================================
Name : homework2.cpp
Author : Mark A. Thompson
Version :
Copyright : 2015
Description : The program performs simple arithmetic operations based on in-
put from the user.
============================================================================
*/
• Function Header Example:
/*
============================================================================
Function : deposit
Parameters : a double representing account balance and a double represent-
ing the deposit amount
Return : a double representing account balance after the deposit
Description : This function computes the account balance after a deposit.
============================================================================
*/
We will be using an electronic homework submission on Blackboard to make sure that
all students hand their programming projects on time. You will submit both (1) the
program source code file and (2) the algorithm design document to the Homework 3
dropbox on Blackboard by the due date and time.
Note that this project must be done individually. Program submissions will be checked
using a code plagiarism tool against other solutions, so please ensure that all work
submitted is your own.
Note that the dates on your electronic submission will be used to verify that you met the
due date and time above. All homework up to 24 hours late will receive a 50% grade
penalty. Later submissions will receive zero credit, so hand in your best effort on the
due date.
As a safety precaution, do not edit your program (using vi or pico) after you have
submitted your program where you might accidentally re-save the program, causing the
timestamp on your file to be later than the due date. If you want to look (or work on it)
after submitting, make a copy of your submission and work off of that copy. Should
there be any issues with your submission, this timestamp on your code on the CSE
machines will be used to validate when the program was completed.
