CS16: Programming Assignment 06

Introduction – Important: Read this!

The assignment for this week will utilize concepts of file I/O data streams and string manipulation.

Again, the TAs and I will be looking for (and grading) programming stylizations, such as proper use of comments, tab indentation, good variable names, and overall block and function designs. So, it is not enough for your lab to pass submit.cs! Please read the instructions herein carefully.

BE AWARE that we will run anti-plagiarism software on this lab. If you are caught cheating by copying code from another student (lab partners excepted) or from a source on the internet, you WILL GET A ZERO ON THIS LAB and maybe a ZERO ON THIS COURSE.

Pair programming is REQUIRED for this lab!!!

You must choose a partner for this lab before you begin! Please consult with your lab TA if you cannot find a partner. No changes will be allowed to your paired grouping once established.

You MUST pair with someone IN THE SAME LAB AS YOU. Both students will submit the same files and get the same grade. In submit.cs, click on the BLUE button that says “Join Groups” before you submit files. Ask your T.A. for help if you need it. In the case where there is an odd number of students in the lab, the T.A. will choose who the un-paired student will be (ONLY ONE student per lab is allowed this).

Choose who will be the first “driver” and who will start as “navigator”, and then remember to switch (at least once) during the lab. But you should probably know the long-term goal too: each partner should participate in both roles in approximately equal parts over the course of the assignment.

DO NOT share passwords. Instead, use scp or email to share files with each other at the end of each work session.

PLEASE MAKE SURE YOU TRADE CONTACT INFORMATION WITH YOUR LAB PARTNER! This means emails, phone numbers, online chat handles, or whatever is necessary to continue working together when you are working remotely. Share your work with each other at the end of EVERY work session.

All lab exercises will be graded for styling as well as any requirements spelled-out below.

Step 1: Getting Ready

Open a terminal window and log into the correct machine. Change into your CS 16 directory, create a lab06 directory and change into it. Remember that at any time, you can check what directory you are currently in with the command pwd.

Step 2: Create and Edit Your C++ Files

This week, you will need to create 2 files called stddev.cpp and rhymes.cpp: Each corresponds to one of the problems listed below, which make up this lab.

Each of the 2 problems is worth 50% of the submit.cs portion of the grade. Each problem should be solved in its own file and each must be submitted for full assignment credit. Note: All these submissions will be checked by the automatic system on submit.cs AND by the instructor and TAs for further evaluation of coding style and meeting requirements. Details below.

STDDEV.CPP

This program takes its inputs from a file that contains numbers. The program reads them in as type double. The program outputs to the screen the standard deviation of the numbers in the file. The file contains nothing but numbers of type double separated by blanks and/or line breaks. The standard deviation of a list of numbers x1, x2, x3, and so forth is defined as the square root of:

((x1 – a)² + (x2 – a)² + (x3 – a)² + …) / (n - 1)

Where the number a is the average of the numbers x1, x2, x3, and so forth and the number n is the count of how many numbers there are. The answers should be given with 3 decimal points precision.

The program has to ask the user for the file name and has to check to see if the file exists (use the string “Enter file name:\n” for the question). If it does not exist, the program must output (via cerr) an error message: “Input file opening failed.” and then exit with code 1.

Your program should define at least one function. If your program does NOT have at least one function, you will not get credit for this part of the assignment, even if your program passes submit.cs grading. And remember that you can ONLY use programming techniques and instructions that we have covered in class so far.

A session should look exactly like the following example (including whitespace and formatting - note that there is no whitespace at the end of each of these lines and each printed line has a newline at the end), with all manners of different numbers for inputs and the output:

Enter filename:
nums.txt
The standard deviation is 1.581

The accompanying input file in this example, could look like this (note the separation by one or more spaces):

6 7 8    9			10

or like this (note the separation by either spaces or newline characters):

6 7
8
9
10

MAJOR REQUIREMENT: At least ONE function.

RHYMES.CPP

Write a program that finds rhyming words in a poem. Specifically, the program reads an input file, line by line, and extracts the last word in each line. It then compares this last word with the last word from the line after it. If it finds that the 2 words “rhyme” (which is simply defined as the 2 words that are being compared share the same 2 last letters), then it prints out these two words to standard output (i.e. the display). But FIRST, the words must be cleaned up of any non-alphabetical characters (usually this means puncuation, since many poems have their last lines often end with a comma, a semicolon, a question-mark, etc…) So if the last word on a line has punctuation marks on it, e.g. “hello?!”, it becomes “hello”. Or if the last word is “don’t”, it becomes “dont”.

Finally, the program has to state how many rhyming pairs it found, or if it did not find any at all.

The program has to ask the user for the file name and has to check to see if the file exists (use the string “Enter file name: “ for the question). If it does not exist, the program must output (via cerr) an error message: “Input file opening failed.” and then exit with code 1.

Your program should define at least one function. If your program does NOT have at least one function, you will not get credit for this part of the assignment, even if your program passes submit.cs grading. And remember that you can ONLY use programming techniques and instructions that we have covered in class so far.

As an example, assume there is a text file called “MyPoem.txt”, which contains this:

"I cannot go to school today,"
Said little Peggy Ann McKay.
"I cannot go to school and play!
I have the measles and the mumps,
A gash, a rash and purple bumps.
My mouth is wet, my throat is dry,
I’m going blind in my right eye.
My tonsils are as big as rocks,
I’ve counted sixteen chicken pox"

(slightly modified from the poem “Sick” by Shel Silverstein)

The program would run as follows:

Enter file name: MyPoem.txt
today and McKay
McKay and play
mumps and bumps
There are 3 pairs of rhyming words.

Note that “dry” and “eye” were not shown, nor were “rocks” and “pox”. This is because they do not meet the program’s criteria of a “rhyme”’. Also note the last line says how many pairs of rhyming words there are. Please make the word “pair” singular if only 1 pair of rhyming words is found and use the plural “pairs” if you found more than 1 rhyming pairs.

Consider another example file called “No.txt”:

No means no, it always means no
If I say it once it means 
A thousand times no!

(slightly modified from the song “No!” by They Might Be Giants)

The program would run as follows:

Enter file name: No.txt
No rhymes found.

Note that no rhymes were found because the program only looks at adjacent lines.

You can assume that the text file containing the poem has at least 2 words per line, that the rhyme comparison is case-sensitive, and that the last words in the line contain at least 2 characters.

You will need to use multiple member functions to manipulate strings in this program. In addition, you will have to use the getline() function in the library in order to read an entire line by ifstream.

MAJOR REQUIREMENT: At least ONE function.

Step 3: Create a makefile and Compile the Codes with the make Command

In order to learn another way to manage our source codes and their compilations, we will first create a makefile and put in the usual g++ commands in it. Afterwards, whenever we want to compile our programs, the Linux command is a lot shorter. The use of makefiles will reveal itself to be very useful the more complex our programs and CS projects become.

Using your text editor, create a new file called makefile and enter the following into it:

all: stddev rhymes

stddev:
	g++ -std=c++11 -Wall stddev.cpp -o stddev

rhymes:
	g++ -std=c++11 -Wall rhymes.cpp -o rhymes

Then from the Linux prompt, you can do one of two things: either issue separate compile commands for each project, like so:

$ make stddev

Or, you can issue one command that will compile all the projects mentioned in the makefile, like so:

$ make

If the compilation is successful, you will not see any output from the compiler. You can then run your programs, for example:

$ ./stddev

If you encounter an error, use the compiler hints and examine the line in question. If the compiler messsage is not sufficient to identify the error, you can search online to see when the error occurs in general.

Remember to re-compile the relevant files after you make any changes to the C++ code.

Step 4: Submit

Once you are satisfied that your programs are correct, it is time to submit them. Login at https://submit.cs.ucsb.edu, then navigate to “CS16_f17” and click on lab06. Then click “Make Submission”, and make your submission the same way as last week. Remember to submit both of the .cpp files.

Please remember that you must submit the programs to obtain any credit for the assignment; just completing the programs is not enough.

Once you submit, you should see a page detailing your submission. The system will automatically grade your program and will show you the results on this page after a 1 minute delay.

You can alternatively submit your code from the command line (terminal) on any CS machine, including the Phelps lab machines or the CSIL server. You can use this method when logged in remotely. To submit the the three source files to this assignment by running the command:

$ ~submit/submit -p 866 stddev.cpp rhymes.cpp

You can copy the URL shown in the output of the above and paste into a web browser to reach the submission result page.

Step 5: Check Submission Results

After the 1 minute delay, the submit system will show your score and give you feedback on your submission. Refresh the webpage after a minute to see this information.

You may submit this lab multiple times. You should submit only after local compilation does not produce any errors and runs as expected. The score of the last submission uploaded before the deadline will be used as your assignment grade.

Step 6: Done!

Once your submission receives a score of 100/100, you are done with this assignment.

If you are in the Phelps lab or in CSIL, make sure to log out of the machine before you leave. Also, make sure to close all open programs before you log out. Some programs will not work next time if they are not closed. Remember to save all your open files before you close your text editor.

If you are logged in remotely, you can log out using the exit command:

$ exit