CS 159 –  Lab #3

CS 159 –  Lab #3
What will you submit? A single C-file will be submitted electronically via the guru server. An example submission was
conducted as part of the Account Configuration Activity. If you have a concern regarding how to submit work, please
contact course staff prior to the deadline for this, and all, assignments. The programming assignment is due on Friday
February 12, 2021 at 11:00pm (LOCAL WEST LAFAYETTE, IN TIME). No late work will be accepted.
Weekly Quiz #3:
The weekly quiz will be available (Week 4 module on Brightspace) until the same date and time that the programming
assignment is due. It is strongly recommended that you complete the attached problems, the programming assignment,
and watch all relevant lectures before attempting the quiz.
The quiz will emphasize chapter 3 material, the written problems in this document, the lab programming assignment, and
the course programming and documentation standards as used in this lab. Quiz questions are presented one at a time and
cannot be revisited. Be sure to save your answers to each question and to finish your quiz to ensure it is submitted for
grading. Most problems on lab quizzes will be multiple-choice or true-false. Each quiz has a 15-minute time limit.
Collaborative Teaming:
• How do I know who is on my lab team?
◦ On-campus students: TAs have contacted their students via e-mail.
◦ On-line students: Visit the Start Here module on Brightspace and locate the Distance Learning Team
Assignment spreadsheet.
• What if a partner does not respond to your communication? Then the remaining active partners need to be
prepared to proceed on the assignment to meet the deadline.
• Groups are expected to communicate to share their ideas when it comes to solving the conceptual and
programming problems associated with this lab. You may find a collaborative document to be a helpful way
to share thoughts on the written problems and to formulate the logic for the programming problem. Other on-line
tools may come in handy when trying to collaborate on specific segments of code, just make sure they protect
your code from being posted publicly! One popular service from previous semesters is codeshare.io.
• As a group you must determine who will make the final submission for your group, when that submission
will be made, and how the concerns regarding submission will be communicated with the other members. Only
one person per group will make submissions for the entire group. The grader for your section cannot be
expected to grade submissions from multiple members of the same group to determine which submission you
actually want graded.
◦ In order for each member of the group to get credit for the programming problem associated with this lab,
their Purdue University e-mail address must appear in the assignment header.
• How might collaboration be useful on this particular programming assignment?
◦ Consider the logic of the problem and the approach of implementing calculations to resemble selection: Is the
radius of the circle the apothem of the polygon as input by the user or does it need to be calculated in another
way? There are two options that correspond with the two options available as the first input to the program.
What expressions can be developed to activate one method for calculating the radius while canceling out the
other?
◦ Refine your process of collaboration: As programs increase in complexity and length it will become
imperative that groups establish expectations of timely communication and that all partners remain current in
course material to be meaningful contributors to lab assignments.
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Solve the following problems related to material found in Chapter 3 and the course standards.
Statement True /
False
The coding assignment for lab #3 forbids the use of selection constructs (if, else if, else, switch), logical operators
(AND, OR, NOT), and relational operators (<, <=, >, >=, ==, !=). TRUE
All of the compound assignment operators share the same level of operator precedence.
Operator precedence can be used to bind operators to operands and from that will determine the order of operations in
an expression.
A single-type operation will generate a result of that same type.
When evaluating an operator with mixed-type operands it is the lower ranked data type that is converted to that of the
higher ranked data type.
The use of a precision modifier when displaying a floating-point value will result in truncating all digits beyond the
specified precision value.
Converting a higher ranked data type to that of a lower ranked data type may result in the loss of data.
Section 3.1
When two operators with the same precedence occur in an expression and their associativity is left-to-right, the left
operator is evaluated first.
An expression always reduces to a single value.
The value of the postfix increment expression is determined before the variable is increased.
The operand in a postfix or prefix expression must be a variable.
The assignment expression evaluates the operand on the right side of the operator and places its value in the variable
on the left.
When a compound assignment is used with an expression, the expression is only evaluated first when parentheses are
used to raise its level of precedence. [Example: x *= (a + b)]
The compound assignment operator (/=) has a higher level of precedence then the addition operator (+).
Section 3.4
The result of an expression is undefined when it attempts to modify a single variable more than once.
Section 3.5
When the types of two operands in a binary expression are different, C automatically converts one type to the other.
When the types of two operands in a binary expression are different, the lower-ranked type is promoted to the rank of
the higher type.
In an assignment statement, promotion occurs if the right expression has a lower rank than the variable on the left and
demotion occurs if the right expression has a higher rank.
An explicit type conversion is the programmer taking control and determining the data type of an operand in an
expression.
To cast data from one type to another, we specify the new type in parentheses before the value we want converted.
Section 3.6
The defined constant results in an automatic substitution of the value that follows the symbol where it is found in the
program. One exception, no such substitution will take place inside of quotes.
Problems associated with defined constants are difficult to resolve as the programmer views the original statement
and not the statement with the error after the substitution takes place.
Section 3.7
One programming technique to simplify code is to use parentheses, even when unnecessary.
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Solve the following problems related to standard library constants and functions:
In which library will you find the abs function? How is this function different from the fabs function found in
math.h?
What is INT_MAX? Where is it defined? What are FLT_MAX and FLT_DIG? Where are these defined?
Identify each of the constants found math.h below:
M_E
M_PI
M_LOG2E
M_LOG10E
M_LN2
M_LN10
Solve the following problems related to material found in Chapter 3.
• 25 % 11
• 49 % 5
• 132 % 2
• 133 % 2
• 134 % 2
• 135 % 2
• 16 % 17
• 2 % 1
Given A and B are integer variables, both are greater than zero, and A is greater than B. What is the result of the
expression below?
• B % A
Given A and B are integer variables, both are greater than zero, and A is less than B. What is the range of values possible
as a result of the expression below?
• B % A
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Lab #3 – Programming Assignment
Due: Friday February 12, 2021 at 11:00pm (time local to West Lafayette, IN)
10 Points Possible
Problem: The user of your program will indicate whether (1) a regular polygon is inscribed inside of a circle or (2) the
circle is inscribed inside of a regular polygon. The number of sides and the apothem will follow as additional input.
Calculate and display both the radius and area of the circle, and the side length and area of the regular polygon.
Requirements of your solution:
• The only functions from math.h that can be used are sqrt, pow, and the trigonometric functions.
• Any use of logical operators, relational operators, bool variables, or selection constructs is prohibited.
• A violation of either of the above will result in your assignment being awarded no points.
The technique necessary to solve this problem with the given requirements is similar to that used in the final two
examples of chapter 3.
Example Execution #1:
1. Polygon inside of circle
2. Circle inside of polygon
Select your option -> 1
Enter number of polygon sides -> 6
Enter length of polygon apothem -> 9
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Circle Radius: 10.39
Circle Area: 339.29
Polygon Side Length: 10.39
Polygon Area: 280.59
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Example Execution #2:
1. Polygon inside of circle
2. Circle inside of polygon
Select your option -> 2
Enter number of polygon sides -> 6
Enter length of polygon apothem -> 20
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Circle Radius: 20.00
Circle Area: 1256.64
Polygon Side Length: 23.09
Polygon Area: 1385.64
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Example Execution #3:
1. Polygon inside of circle
2. Circle inside of polygon
Select your option -> 2
Enter number of polygon sides -> 5
Enter length of polygon apothem -> 138.83
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Circle Radius: 138.83
Circle Area: 60550.33
Polygon Side Length: 201.73
Polygon Area: 70016.06
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Example Execution #4:
1. Polygon inside of circle
2. Circle inside of polygon
Select your option -> 1
Enter number of polygon sides -> 5
Enter length of polygon apothem -> 55.71
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Circle Radius: 68.86
Circle Area: 14897.07
Polygon Side Length: 80.95
Polygon Area: 11274.50
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Example Execution #5:
1. Polygon inside of circle
2. Circle inside of polygon
Select your option -> 1
Enter number of polygon sides -> 12
Enter length of polygon apothem -> 9.93
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Circle Radius: 10.28
Circle Area: 332.02
Polygon Side Length: 5.32
Polygon Area: 317.05
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
All course programming and documentation
standards are in effect for this and each
assignment this semester. Please review this
document!
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Additional Requirements:
1. Add the lab assignment header (vi shortcut hlb while in command mode) to the top of your program. An
appropriate description of your program must be included in the assignment header.
Include the Purdue University e-mail addresses of each contributing group member in the assignment header!
2. Each of the example executions provided for your reference represents a single execution of the program.
Your program must accept input and produce output exactly as demonstrated in the example executions, do not
add any “bonus” features not demonstrated in the example executions. Your program will be tested with the data
seen in the example executions and an unknown number of additional tests making use of reasonable data.
◦ All floating-point variables must be of the double type.
◦ Use the constant value M_PI where needed for the constant pi.
◦ The number of sides of the regular polygon will always be an integer greater than 3.
3. Course standards prohibit the use of programming concepts beyond the material found in the first three chapters
of the book, notes, and lectures to be acceptable for use.
◦ Any use of logical operators, relational operators, bool variables, or selection constructs is prohibited
and would violate requirements of this assignment resulting in no credit being awarded for your effort.
◦ All code for this assignment will be placed inside of the main function. User-defined functions will
be a requirement beginning with lab #4.
4. A program MUST compile, be submitted through the guru server prior to the posted due date to be considered
for partial credit. The C-file you submit must be named exactly: lab03.c
Course Programming and Documentation Standards Reminders:
• Maximize your use of symbolic/defined constants and minimize your use of literal constants.
• Indent all code found within the main function exactly two spaces.
• Place a single space between all operators and operands.
• Comment all variables to the right of each declaration. Declare only one variable per line.
• Notice that several programs (see program 2-9 on pages 74-75) in the programming text use a single line
comment to indicate the start of the local declaration and executable statement sections of the main function.
◦ At no point during the semester should these two sections ever overlap. You might consider adopting this
habit of commenting the start of each section to help you avoid this mistake.
• Select meaningful identifiers (names) for all variables in your program.
• Do not single (or double) space the entire program, use blank lines when appropriate.
• There is no need to include example output with your submission.
Auto-Grade Tool
• We have implemented what is being referred to as the auto-grade tool. At the time of a successful assignment
submission you may receive some feedback on your program in regards to course programming and
documentation standards. This feedback may include a potential deduction that you will receive once your
assignment is reviewed by your grader.
• It is expected that graders verify those notes identified by this tool to ensure that they are indeed applicable and
reasonable to the submission. Graders may make additional deductions for those standards not identified by the
new tool.
• We hope that this feedback helps with the enforcement of course standards, consistency in grading across
sections, and to encourage students to revise their work when problems are identified before the assignment
deadline passes. It is possible to resubmit an assignment for grading up to the advertised deadline. Only the final
successful submission is retained and evaluated.
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