Fall Back Son

void UseArray (int a [])
void UseArray (int *a)

apparently these are the same. I have a guess why, so I'll say that, and hopefully someone will be kind enough to tell me if I'm wrong (and what the real reason is, if so).

void UseArray (int a []):
Passed the address of the array to the function UseArray.

void UseArray (int *a):
Passes the thing the pointer points to (the value of a) to the function, and by doing so, also passes the address of a.

Jimbo

You might want to check out DaWei's or Narue's articles on pointers.

[edit:] They're both really long, but both do address the difference between arrays and pointers

__________________
<insert disclaimer here>
<insert shameless plug for Visual Studio here>

andro

If A[N] and *(A+N) mean the same thing...

&A[N] == &*(A+N)

&A[N] == (A+N)

Set N to 0

&A[0] == (A+0)

&A[0] == (A+0) == A

kurifu

I have never seen anyone solve a pointer like that before, lol.

__________________
Clifford Matthew Roche &lt;geek@cliffordroche.com&gt;
Web Hosting: http://www.crd-hosting.com
Consulting: http://www.crdev-consulting.com

DaWei

It's just as well you haven't.
Good thing the IF is there; they don't mean the same thing.

__________________
Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code.
Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers

grumpy

The short explanation is that, by convention, the C compiler treats the name of an array like it is a pointer and, conversely, a pointer like it contains the address of the first element of an array, in some circumstances.

DaWei

A longer explanation can be found by referring to the C++ standard:
The equivalency of the two, under some conditions, is due to a conversion, not an identity. You can see this clearly if you write the relevant code and examine the emitted machine code. This is akin to an integer being converted or promoted to a double, without a cast, if you write the code correctly.

__________________
Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code.
Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers

bl00dninja

so for:


for a lot of operations would it be more efficient to use:


instead of:


??????????????????????

i am rather curious about this now.

__________________
i put on my robe and wizard hat...

Have you ever heard of Plato, Aristotle, Socrates?...Morons.

grumpy

Not quite, bl00d. For some use cases, "x[0]" and "*x" have the same meaning. Or, alternatively, "x" and "&x[0]" have the same meaning.

Keep in mind that an array and a pointer are different things. We're talking about cases where the compiler converts one into the other so they appear to be the same.

Fall Back Son

thanks for the replies everyone