"Noah Spitzer-Williams" wrote on 23 Sept 03:

Hello guys,

I'm itinerating through my array using pointers in this fashion:

image is unsigned char image[]

do {

cout << "image byte is: " << *image << endl;

while (image++);


Now my problem is sometimes i don't just want to do image++, i

want

to jump around in image but to know where i want to jump to, i need

to

know which element i'm on (the 1st element image[0], 3rd, 54th?)

Is there anyway I can do this? Basically what I'm trying to do is
this:

while (image = (image + skip) % some int's)

So as you see, the location where I want to jump relies on where

I

currently am.

Thanks!

- Noah

As long as I understand you're situation correctly, it's simple.

// your array with 'n' elements:
unsigned char image[ n ];
// pointer you use to access the elements of 'image':
unsigned char* p = image;

// current location in array:
unsigned long i = 0;
p[ i ] = some_new_value;
// move to a different location by a
// fixed amount (limited to array bounds)
i = (i+skip_size) % n;
p[ i ] = some_other_value;
// call function that requires address
// of current array element
useAddress( p );

If you really don't need the pointers, or &image[ i ] will suffice
when you need an address, you could make the above cleaner by losing
the pointer and subscripting the array directly:

// your array with 'n' elements:
unsigned char image[ n ];

// current location in array:
unsigned long i = 0;
image[ i ] = some_new_value;
// move to a different location by a
// fixed amount (limited to array bounds)
i = (i+skip_size) % n;
image[ i ] = some_other_value;
// call function that requires address
// of current array element
useAddress( &image[ i ] );

I hope I understood the situation properly so this is actually
relevant,
Mike

Hi,

Why not directly access the image array as:
for (int i=0;image[i];i++)
{
cout << image[i];
}

"Noah Spitzer-Williams" <noahsw@cyberdude.com> wrote in message
news:3dc5ea8a.0309222251.5215d28@posting.google.com...

Hello guys,

I'm itinerating through my array using pointers in this fashion:

image is unsigned char image[]

do {

cout << "image byte is: " << *image << endl;

while (image++);


Now my problem is sometimes i don't just want to do image++, i want
to jump around in image but to know where i want to jump to, i need to
know which element i'm on (the 1st element image[0], 3rd, 54th?)

Is there anyway I can do this? Basically what I'm trying to do is
this:

while (image = (image + skip) % some int's)

So as you see, the location where I want to jump relies on where I
currently am.

Thanks!

- Noah

Hi,