Re: 2 dimensional arrays

From: Francis Glassborow (francis_at_robinton.demon.co.uk)
Date: 08/31/04 

Date: 31 Aug 2004 08:08:31 -0400
To: (Usenet)

In article <opsdind2n6win0yh@news.zebratelecom.ru>, Ivan Korotkov
<clcppm-poster@this.is.invalid> writes
>Or better this:
>
>int (*pi)[3] = new int[2][3];
>
>The former method loses in performance (because each array access needs
>two derefernces). The latter one doesn't, it's just the same as { int
>pi[2][3]; }

I'd prefer to see '3' replaced. Either by:

int const row_length(3);

or:

typedef int row[3];
row * array(new row[2]);

Or even better, do both:

int const row_length(3);
typedef int row[row_length];
int const rows(2);
row * array(new row[rows]);

typedefs are a good way to handle 'magic' types. 

--
Francis Glassborow      ACCU
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