CS 117, Winter 1997

Assignment 2: Words, due Wednesday 4/8/98

You may work with a partner for this assignment. No groups of three or more, please.

When you are done with this assignment, please submit it using the Homework Submission Program.

The problem

I often want to collect some statistics on my writing. If I'm writing a proposal that has to be shorter than 2000 words, I will want to count the number of words in each of my drafts. If I'm trying to write software documentation at a sixth-grade reading level (tragically, that's what the software experts usually recommend), I'll want to keep an eye on the number of letters and syllables in my words, the number of words in my sentences, and the number of sentences in my paragraphs.

Actually, I just like fooling around with this kind of thing. It pleases me to know how many words there are in Middlemarch, or how many times the word "whilst" appears in Hamlet (326398 and 4, respectively, by the way).

For this assignment, you will write a program that takes a text file as input and reports

For now, we won't look at syllables, sentences, or paragraphs.

A little more detail

When you compile your program (g++ -Wall -o words words.cpp or something similar) and run it like so: 

  words < somefile.txt

your program should produce an easy-to-read report that looks something like this: 

   Number of words: 1729
   Average word length: 5.72 letters
   Longest word: electroencephalography (22 letters)
   Shortest word: a (1 letter)
   Occurrences of "the": 62
   Alphabetically latest word: zygomorphic

A small offering

You might be surprised to learn that the hardest part of writing this program is reading one word at a time out of the input file. Punctuation, extra spaces, ends of lines, and the end of the file itself can all cause trouble if you aren't careful. With this in mind, I have written a C++ function GetWord to help you out. You can see how it is used in the laboratory exercise getword.cpp. Here is GetWord itself: 

//////////////////////////////////////////////////////////////////
//
//	GetWord retrieves the next word from standard input (cin),
//	returning true if there is a word remaining in the input,
//	and false if not.  In the former case, the word is
//	returned via the reference parameter "word".
//
//	GetWord defines a "word" to be any contiguous block of 
//	letters, hyphens, and apostrophes.  Thus, "don't" and
//	"willy-nilly" are both considered words (as they 
//	should be), but so is "--'--xxxx-'".  Defining "word" 
//	better than this is possible, but complicated.
//
//	We'll talk about how GetWork works some time in class.
//
//////////////////////////////////////////////////////////////////

bool GetWord( string& word )
{
	char	c;
	
	cin.get( c );
	while( !cin.fail()  &&  !isalpha(c)  &&  c != '-'  &&  c != '\'' )
		cin >> c;
	
	if( cin.fail() )
		return( false );

	word = c;
	cin.get( c );
	while( !cin.fail()  &&  (isalpha(c) || c == '-' || c == '\'') )
	{
		word = word + c;
		cin.get( c );
	}
	
	return( true );
}

That's all

Make sure to include a comment at the top of your program giving your name, the date, and a brief description of what your program does.

Start early, keep in touch, and have fun.


Jeff Ondich, Department of Mathematics and Computer Science, Carleton College, Northfield, MN 55057
(507) 646-4364, jondich@carleton.edu