Size of numeric array (in C)

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February 14th, 2004, 08:45 PM

schorsche

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Size of numeric array (in C)

Hiya!

To get the size of a char array, the command
strlen(chararray) does the job.

But is there a command that returns the size of
an int array?

Many thanks

February 14th, 2004, 08:51 PM

gdjsmith

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The sizeof() will tell you how much memory has been alloted to the array then you could divide by the sizeof(type) to determine how many elements can fit into that array. But to find out how many elements have been stored in that array.... I've never heard of a built-in function like say intlen() or something??

February 14th, 2004, 08:57 PM

schorsche

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Yeah me neither...intlen() doesn't seem to exist. The sizeof() approach seems to be the best way...thanks!

February 14th, 2004, 09:03 PM

Ancient Dragon

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To get the size of a char array, the command
strlen(chararray) does the job.
No, the strlen() only returns the length of the string stored in the array. The size of the array could be a lot bigger than that.

But is there a command that returns the size of
an int array?
use sizeof operator, as other posters have mentioned.

February 15th, 2004, 12:29 AM

infamous41md

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#define intlen(x) ( sizeof(x) / sizeof(int) )
or better yet
#define alen(x, type) (sizeof(x) / sizeof(type) )

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February 15th, 2004, 03:52 AM

Analyser

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The following works too, with the added benefit of not having to supply the type.

Code:

#define ALEN(a) (sizeof(a) / sizeof((a)[0]))

Bear in mind that any of the macros presented in this thread thus far work only on arrays declared at compile time. If you use malloc() et al, all these macros are useless!

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February 15th, 2004, 05:23 PM

schorsche

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Cool! That answers all my questions!

Cheers

Size of numeric array (in C)

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