Due: Sunday, 4 February 2018, 11:59 PM on TEACH as a .cpp
Error Handling and Helper Function Library
Users are seldom perfect. It is our job as programmers to catch mistakes and correct them to
prevent crashing the program. The table below illustrates common functions you will use for
error handling and working with user in the CS 16X series.
Design (Recitation)
You will design solutions to each of the functions outlined in the table. Make sure to include a
Understanding the Problem section and a Testing section in your design. Please consult the
design syllabus for additional information. Tips for designing this assignment:
● Don’t worry about functions to start
● Treat each function as a mini program
● Design the solution to each problem using loops, conditionals and what you know about
strings
● Could be helpful to put each solution on a notecard to simulate a function
● During week 3 you do not need to know about functions to successfully design solutions
to each problem
(50 pts) Implementation
Implement each function in the table. You are not permitted to use any built in functions. You
may use the string library and string type but you are not permitted to use any of the other helper
functions found in that library. You are encouraged to use the ASCII chart.
Grading:
● Each function is worth 3 points.
● You will receive 2 points by default.
● All functions must follow the outlined naming conventions, input and output values
shown below in the table. Failure to do so will result in a zero for that function.
Function Name Input
(Parameters)
Output (Return
Type)
Description/Notes
check_range int lower_bound
int upper_bound
int test_value
Boolean Indicates if the
provided number is in
the specified range
is_int string num Boolean Indicates if a given
string is an integer
is_float string num Boolean Indicates if a given
string is a float
is_capital char letter Boolean Indicates if a given
character is a capital
letter
is_even int num Boolean Indicates if a given
number is even
is_odd int num Boolean Indicates if a given
number is odd
equality_test int num1
int num2
Int Tests num1 against
num2 and returns -1 if
num1
num2
float_is_equal float num1
float num2
float precision
Boolean Tests if num1 and
num2 are equal to
each other within a
certain precision
numbers_present string sentence Boolean Indicates if the
provided string
contains numbers
letters_present string sentence Boolean Indicates if the
provided string
contains letters
contains_sub_string string sentence
string sub_string
Boolean Indicates if substring
exists in sentence
word_count string sentence Int Provides the number
of words in a given
string
to_upper string sentence String Capitalizes all letters
in a given string and
leave all non-letter
characters unchanged
to_lower string sentence String Makes all letters
lowercase in a given
string
get_int string prompt Int Takes a prompt from
the user as a string
literal, checks if input
is a valid integer,
returns the provided
integer
get_float string prompt Float Takes a prompt from
the user as a string
literal, checks if input
is a valid float, returns
the provided float
(35 pts) Testing
Main() will serve as the location where you test your functions. For each function you must show
each return option is reachable. For example, is_int() should be run twice: once to show that it
can successfully identify a string as an int and return true; once to show that is can successfully
identify the string is not an int and return false. You must label your tests, indicating what you
are testing, the value you are providing, the expected output and the actual output. If the
expected output matches the actual output, the program should print “PASS” for the test and
“FAIL” otherwise. Your print out should be readable. 28 points come from the actual tests (one
for each return). The remaining 7 points comes from clean output (how readable the print
statements are).
(15 pts) Program Style/Comments
In your implementation, make sure that you include a program header and function headers in
your program, in addition to proper indentation/spacing and other comments. Below is an
example header to include. Make sure you review the style. guidelines for this class, and begin
trying to follow them, i.e. don’t align everything on the left or put everything on one line!
http://classes.engr.oregonstate.edu/eecs/winter2018/cs161-001/assignments/161_style_guideline.
pdf
/*********************************************************************
** Function:
** Description:
** Parameters:
** Pre-Conditions:
** Post-Conditions:
*********************************************************************/
(10 points) Extra Credit (Choose One)
Option 1:
The above functions solve problems you will likely face in future assignments. One method for
reusing these functions is to copy and paste them into each assignment. A better way is to make
this set of functions into a library which you can include in future assignments but this is a
concept we do not usually cover until CS 162.
Using the link below for reference, create your own library from these functions by separating
your assignment into three files: helper_functions.h, helper_functions.cpp, and assignment3.cpp
Include the helper_functions.h in your assignment3.cpp and compile using the following line:
g++ assignment3.cpp helper_functions.cpp -o assignment3
Resources (start on slide 7):
http://classes.engr.oregonstate.edu/eecs/spring2017/cs162-001/calendar/slide2-notes.pdf
Option 2:
Testing is a very important part of programming. Fully test your is_int and is_float functions.
Test as many inputs as you can imagine. See how you can break your functions and if you do
how are you going to fix it. Use the following hints to get you started:
● What happens if you have multiple digits?
● What happens if there is a sign at the beginning/end?
● What happens if it is a string with letters and numbers?
● What if you don’t supply digits after a dot?
Record your tests cases the same way you did in main.
Electronically submit your C++ program (.cpp file, not your executable) by the assignment due
date, using TEACH.
https://secure.engr.oregonstate.edu:8000/teach.php?type=want_auth
Make sure you demo Assignment #3 within two weeks of the due date to receive full credit.
If you go outside the two week limit without permission, you will lose 50 points. If you fail
to show up for your demo without informing anyone, then you will automatically lose 10
points.