comparing 2 txt files

**norhos** · 03-13-2008

Hi, i have two text files file-a and file-b and i would like to compare the the text of file-a to file-b. the format of file-a is just like a normal essay paragragh and file-b is one word per line. right now what i did was to use fscanf to run through each word in file-a and compare it with file-b. How can i actually pick up a word from file-a and ommit special characters like (,-,+?
e.g happy+ will jus extract happy instead of happy+... and instead of comparing each word through file-b one by one, is there a better way for me to optimize the speed of the comparison?

**JFonseka** · 03-13-2008

while (((c=getchar()) && ((c != ',') || (c != '+'))) {

That way once the word is being read from file a, it will skip the special characters and copy it to b?

**JFonseka** · 03-13-2008

I think better still is to say

while (((c = getchar()) && (((c >= 'A') || (c <= 'Z')) || ((c >= 'a') || ((c <= 'z'))))))

Not sure about the brackets, check with your editor.

This way it only gets the alphabet characters, if you need the numerical characters, then you need to add that to the list as well.

**norhos** · 03-13-2008

ic ic.. how about any way to speed up the search? will a link link do the job?

**JFonseka** · 03-13-2008

Originally Posted by norhos

ic ic.. how about any way to speed up the search? will a link link do the job?

Well what exactly is your algorithm for comparing the words?

**Elysia** · 03-13-2008

Originally Posted by JFonseka

while (((c = getchar()) && (((c >= 'A') || (c <= 'Z')) || ((c >= 'a') || ((c <= 'z'))))))

Wow. Horrible code

I think is along the lines of how you want (made the above code a little more readable):

Code:

while
(
	( c = getchar() ) != EOF && 
	(
		( (c >= 'A') || (c <= 'Z') ) ||
		( (c >= 'a') || (c <= 'z') )
	)
)

However, I think it might be simplified to this:

Code:

while
(
	( c = getchar() ) != EOF && isalpha(c)
)

**JFonseka** · 03-13-2008

Originally Posted by Elysia

Wow. Horrible code

I think is along the lines of how you want (made the above code a little more readable):

Code:

while
(
	( c = getchar() ) != EOF && 
	(
		( (c >= 'A') || (c <= 'Z') ) ||
		( (c >= 'a') || (c <= 'z') )
	)
);

However, I think it might be simplified to this:

Code:

while
(
	( c = getchar() ) != EOF && isalpha(c)
);

I think it's in times like this we say:

"Thanks Elysia. You're a programming master! How the hell do you know every thing?"

Now that poor bugger probably implemented what I gave him and got his while loop to not end since no EOF was there and probably still working out the brackets.

Remind me not to advise anyone, lol.

**Elysia** · 03-13-2008

Oh yeah, and if you want to include numbers, it becomes something like

Code:

while
(
	( c = getchar() ) != EOF && isalpha(c) && isdigit(c)
)

Oh and disregard (remove) the ; at the end, in case you added it. I only added it myself to get the code compiling in my IDE.

**JFonseka** · 03-13-2008

And of course for that you need the ctype library. I hope.

**Elysia** · 03-13-2008

Yep, ctype.h for C.

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