How can I print the number of elements in this array?

[steals10304]

How can I print the number of elements in this array?

void GetSubString(const char *source)
   
while ( *source )
   {
      printf("%c", *source);
      ++source;
   }

int main(void)
{

GetSubString("character");

return(EXIT_SUCCESS);
}

[Sebastiani]

Set a counter to 0 and increment it on each iteration of the loop.

[MK27]

I actually just posted a snippet to do exactly that in your other thread.

[steals10304]

Is there a way to do it without declaring a variable. And if you must declare one it must be a pointer?

[MK27]

Is there a way to do it without declaring a variable. And if you must declare one it must be a pointer?

You can also just declare an int as a pointer and still use, but probably that is not the right idea.

Basic "pointer arithmetic":

int stringLength (char *ptr) {
	char *i=ptr;
	while (*i !='\0') i++;
	return i-ptr;
}

*i is synonymous with i[0].

[Elysia]

Is the OP incapable of doing such a simple thing that you must point out a solution to such a basic problem?

[MK27]

Is the OP incapable of doing such a simple thing that you must point out a solution to such a basic problem?

I guess the OP could not, or the OP would not be asking that question in a "programming advice forum"*.

*at least, I think of it as such.

[Elysia]

Then, is it not more common to point out that we don't do homework and refuse to answer?

[MK27]

Then, is it not more common to point out that we don't do homework and refuse to answer?

This homework is far from done. I was just demonstrating a simple technique (pointer arithmetic). I could have just said "use pointer arithmetic" and the OP would have googled and found the exact same example, or looked in his/her textbook and found it there. What's the difference? S/he still has to come to an understanding in order to incorporate the technique into the assignment.

I mean, figuring stuff out for yourself is always the best way. But if I picked up a programming book that had no example code at all in it, I would put it back down again.

[Elysia]

This homework is far from done.

I'd say it's 90% done now.

I was just demonstrating a simple technique (pointer arithmetic). I could have just said "use pointer arithmetic" and the OP would have googled and found the exact same example, or looked in his/her textbook and found it there. What's the difference? S/he still has to come to an understanding in order to incorporate the technique into the assignment.

I would have suggested that the OP use a flowchart or pseudo code. It's not exactly hard to figure out. Upside: programmer learns how to do it and writes the code.

I mean, figuring stuff out for yourself is always the best way. But if I picked up a programming book that had no example code at all in it, I would put it back down again.

So very true, but a good book would thoroughly explain how these examples work, and had the OP read that, he/she would probably not ask this question...

[roaan]

You can also just declare an int as a pointer and still use, but probably that is not the right idea.

Basic "pointer arithmetic":

int stringLength (char *ptr) {
	char *i=ptr;
	while (*i !='\0') i++;
	return i-ptr;
}

*i is synonymous with i[0].

This is a good way of finding the length. Till now i had been using counters but never pointers.

[MK27]

I would have suggested that the OP use a flowchart

[MK27 gets back into chair and wipes "happy hour" spittle off keyboard]

Yes, a flowchart would be *the perfect* way to explain and/or carefully -- but not explicitly -- guide the OP toward the topic of "pointer arithmetic".

You know, maybe the reason I learned C so fast was because I wasn't in school so I could spend time at cboard and, in complete honesty, not be cheating on homework. I don't think being a real student of a real institution should be a such a penalty...

This is a good way of finding the length. Till now i had been using counters but never pointers.

Pointer math comes in pretty handy sometimes. It may also be slightly faster altho I really have no idea one way or the other (I guess that might be an "ASM forum" question

[laserlight]

Pointer math comes in pretty handy sometimes. It may also be slightly faster altho I really have no idea one way or the other

It would be slightly faster, except that making that difference disappear by converting the index version into the pointer version is an optimisation that can be expected of a good (or even mediocre?) optimising compiler.

[cpjust]

Is there a way to do it without declaring a variable.

Of course, just use strlen( source );