Re: need some help

Fred Kleinschmidt said:


"Richard Heathfield" <invalid@xxxxxxxxxxxxxxx> wrote in message
news:dcqdncLBzsurHBTZRVnytQ@xxxxxxxxx
ash said:

hi friends,
i have some questions whch is in my last year question papers.i need
some help to get logic of these questions.

1) write a C function, that takes two strings as arguments and returns
a pointer to the first occurrence of 1st string in 2nd string or NULL
if it is not present.

Well, that one's easy, at any rate.

#include <string.h>
char *ashstrstr(char *haystack, char *needle)
{
return strstr(haystack, needle);
}

This is wrong. It should be strstr(needle, haystack).

<sigh> The easy ones are always hardest.

The instruction was to find first occurence of s1 in s2.
strstr finds first s2 in s1.

Quite right. My apologies.

For this homework, I think the instructor really wants
the student to write the internals of strstr.

Yes, but here in comp.lang.c we try to get the OP to think, rather than
spoonfeed them a solution. In this case, I was trying to get him (or
possibly her - I haven't checked) to think about how to phrase the
question. Shame I messed up the answer, though...

If so, he/she
should have explicitly stated that using strstr was not allowed.

Precisely so.

<snip>

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)
.

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