reading strings from .txt and entering in an array

**matsp** · 12-01-2007

It looks fine to me.

Also, I created a file with 500000 "words" [a, b, c .. z, aa, ab, ac... ba, bb, bc,... zz, etc]

the last ten are

Code:

qqkba
rqkba
sqkba
tqkba
uqkba
vqkba
wqkba
xqkba
yqkba
zqkba

I then instrumented the code to measure the time it takes to read the words in, and it toook about 0.05 seconds the first time round, and 0.16 s the second time round. So although I agree that it's inefficient to read the file twice, it's not as bad as it may seem.

This of course assumes you're not reading the data from a network, slow CDROM or some such - in that case, I'd recommend copying the file to some local storage first.

--
Mats

**trancekid** · 12-01-2007

Originally Posted by Elysia

Haha, must be getting tired. Missed that part.
You're right obviously. You outsmarted your teacher

However... scanf("%s", ...) is unsafe. There's still one thing to fix

And you can still do dynamic memory allocation (though it's a bit more advanced). So there's plenty more work to do if you want it.

Thanks. I appreciate all of the advice. This was only the first part of the assignment, the real part is to set all this into a binary tree (I am using an AVL tree) and a hash table with options for the user to spell check and or delete words from a supplies .txt. Once I can finish the more difficult parts, if I still have time I will come back and fix the allocation and scanf.

**Elysia** · 12-01-2007

So yes, it's an optional optimization the OP may do.
Also noticed fgets(wordString, 30, file) <--- it's better to do fgets(wordString, sizeof(wordString), file).
I don't know if I can think of anything else.

**trancekid** · 12-01-2007

Originally Posted by Elysia

So yes, it's an optional optimization the OP may do.
Also noticed fgets(wordString, 30, file) <--- it's better to do fgets(wordString, sizeof(wordString), file).
I don't know if I can think of anything else.

Ah! good idea!

Updated that as well.

Edit: hey I may have been a pain in the ass but at least I didn't post my assignment and ask someone to finish it all for me, yah? haha. Thansk again Mats and Elysia

**matsp** · 12-01-2007

Not a pain at all.

I expanded my test-input to 5M words, to make the time a bit more measurable. Using realloc and reading the file once takes 1.69s.

Reading the file twice, takes 0.61 + 1.67s. So there's a little bit of time to be gained by not reading it twice - but I think it's too small a gain to really worry about it.

--
Mats

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