strings, arrays, functions, loops and conditionals

Programming Project 1

General: This project will give you a chance to dust off all the cobwebs on your
programming skills. The project requires that you understand characters and
strings, arrays, functions, loops and conditionals (all prerequisite knowledge).
However, just because this is technically “a review”, don’t assume it’s easy!
You’ll write a very simple spell checker. You must produce the output EXACTLY
as specified in this document.
There is some flexibility permitted in your solution to encourage you to adopt
your own ideas for an algorithm. The limits to that flexibility are explained below.
Any extra output, or output that is inconsistent with these requirements will result
in lost points.
Your Mission: Edit the file “Project1.cpp”. You must implement the function
spellCheck. You may find it useful to write several other functions as well. In
fact, I encourage you to avoid writing the whole project as one big (ugly)
function. You will find big (ugly) functions are very difficult to debug, and we will
find it very difficult to help you. For this assignment, you should keep all your
functions in one file – Project1.cpp. They should all be C, and you should not
use C++-only features.
There is only one stage on this project, writing the spellCheck routine. The
spellCheck function has two parameters. The first parameter (article[]) is a
pointer to an array of characters. The contents of this array are an article that
you need to spell check. The end of the article is marked with the normal 0
(marking the end of a string). Thearticle includes punctuation, upper and lower
case words, numbers, and abbreviations. Your function must print every word in
the article that cannot be found in the dictionary. The dictionary is the second
parameter to the function (more on this later).
For this project, a word is a sequence of two or more letters with no intervening
punctuation, numbers or other non-letters. The character immediately preceding
the first letter in the word must not be a letter, or it must be the beginning of the
article. The character immediately following the last letter in the word must not
be a letter, or it must be the end of the article. So, for example, if the article
were, “The red firetruck went round a corner at 50mph”, there would be eight
words (the, red, firetruck, went, round, corner, at, mph). Note that “truck” doesn’t
count because it is embedded inside “firetruck” (the character immediately
preceding ‘t’ is a letter). Note that “a” is not a word because it is not at least two
letters long. And finally, note that mph is a word even though the character
preceding the ‘m’ is not a space. Words don’t have to be preceded by a space,
just by something other than a letter (or the start of the article, of course).
These rules are intended to make finding words EASY. Just look for a letter, that
marks the beginning, and keep scanning for consecutive letters. When you run
out of letters, that marks the end.
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For each word in the article, you must see if there is a matching word in the
dictionary. The dictionary is also a character string. The end of the string is
marked (as always) with a 0. The end of each word is marked with a ‘\n’. A
word in the dictionary can contain any character (other than the ‘\n’ character).
That means the dictionary can contain words like “don’t” or “can’t”. Naturally,
words from the dictionary that have non-letter characters in them (like “don’t”) will
never match a word from the article. Such words
can still appear in the dictionary. All words in the dictionary are sorted in
alphabetical order.
For this project, a word in the article matches a word in the dictionary if the
characters from the two words are the same except for the case of the letters. So
“cAT” and “Cat” match each other, while “Id” and “I’d” do not match each other.
For every word in the article, determine if there is a matching word in the
dictionary. If there is a matching word, do nothing. If there is not a matching word
in the dictionary, print the word from the article.
You can print the words in several ways, depending on how you store the words
in memory. If the word is terminated with a 0 like a regular string, then you can
use printf:
printf(“%s”, word);
If your strings are not terminated with the zero, then you will need to print them
one letter at a time (using a loop). You can print a single letter in one of two ways:
printf(“%c”, letter);
or
putchar(letter);
When you’re debugging your program, you will want to make sure that all the
characters you have printed show up on the screen. That may sound silly, but it
is a real problem. The computer does not always put characters on the screen,
even if you’ve used printf or putchar to print them! If you want to make sure
characters have been forced to the screen, print a new line (“\n”) or use
fflush(stdout).
OUTPUT REQUIREMENTS: Your function must only print the misspelled
words from the article. Each word that you print must be printed on a line by
itself (i.e., you must print a ‘\n’ after each word of output). You may print words in
all lower-case, in all upper-case or in mixed case. The case (upper/lower/mixed)
that you print the word does not need to match the case that is used in the
article. Finally, you must only print words that (a) satisfy the definition of being a
word for this project (see above) and (b) do not appear in the dictionary. If the
same misspelled word appears more than once in the article, then you may print
that word exactly one time, or you may print that word as many times as it
appears in the article. Your program must produce no output other than the
misspelled words (one word per line). Please keep in mind that we will test your
program with different articles and different dictionaries than have been provided
to you. Your program should work with any article or dictionary that satisfies the
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requirements listed above. Not all articles start with a letter or end with a letter.
Not all articles have at least one word. Not all dictionaries have at least one
word.
Guidance/Advice
We strongly recommend that you develop the project in phases. Your first goal
should be to produce a working program that correctly reads (and prints) all the
words from an article. Print the words regardless of whether the word is spelled
correctly or spelled incorrectly. Don’t just sketch pseudo-code of this phase –
really write it, compile it, run it and debug it. Once you can discover and print
each word from the article, proceed to the next phase of development where you
begin consulting the dictionary for each word and printing the word(s) only when
it is misspelled. It is a truism for EE312, if you can make the time to write each
program twice (even if you don’t build all the functionality into your first version of
the program) you will learn more and learn more quickly than if you try to do the
entire project at once.
Project 1 requires no knowledge of pointers. If you are very comfortable with
pointers, feel free to use them. If you are not comfortable, then don’t use them.
The solution to the project has exactly zero occurrences of “*” in the .cpp file (no
kidding). Don’t use variable length arrays in your solution. Think about what size
you want to make your arrays.
Finally, when we are considering the bonus point for Project 1, we are looking
for a combination of good program design (good coding style, including
comments, indentation and variable/function names as well as a concise
implementation of the required functionality), and a robust implementation (your
program works correctly under all reasonable sets of input). Good luck!
Submission
You must include header.c at the top of your submission file. Then submit
Project1.cpp only. If Canvas renames your file because of multiple
submissions, that’s OK.
FAQ
Q: What files do I copy over to kamek.ece?
A: Copy over Project1.cpp, Makefile, the input .txt files – everything in the
starter_files directory. Don’t copy stuff from your CLion folder except your
source code.
Q: I am getting an error related to C++11.
Q: On kamek, you should type in the command ‘module load gcc’ each time you
log in.
A: The makefile is giving strange errors!
A: First, if you are on a 64 bit computer, go into the Makefile and remove the -
m32 flag. Just search for it and remove all instances of it.
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If it still doesn't work, try using
touch Project1.cpp
This updates the timestamp on your file.
Then try
make clean
make
This rebuilds the project from scratch.
Q: How can I test and debug my project?
A: You can test it by typing in
make test
in your terminal. This runs the created executable with the given input file.
Make sure to write your own tests, though.
Debugging is a little trickier. You can use your IDE's debugger, or text-based
GDB, or for now you can use printf to output variables you want to see to the
terminal.
Q: Are we allowed to call functions we write in the same file?
A: Please do! Using one function would be harder to read. Just know that we
won't call them from our main while testing.
Q: What do I submit?
A: Submit your Project1.cpp file. Make sure that all your functions are in this
one file.
Q: May I use the C++ standard library?
A: No. You may use the standard C library, but you don't have to.
Q: What is a segmentation fault?
A: A segmentation fault means your program tried to access an address that it
couldn't get to. This usually means you tried to read past the end of a string, but
it could be any invalid memory access.
Note that the files look something like this to your program:
Dictionary:
word1\nword2\nword3\n....lastword\n\0
Text file:
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word1 word2'word3\nword4....\0
CHECKLIST – Did you remember to:
¨ Re-read the requirements after you finished your program to ensure that
you meet all of them?
¨ Include the header file (filled out) at the top of your submitted file?
¨ Make sure that your program passes all our testcases?
¨ Make up your own testcases?
¨ Upload your solution to Canvas?
¨ Download your uploaded solution into a fresh directory and re-run all
testcases?
¨ Check that your solution works on kamek.ece?