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From: turk@Apple.COM (Ken "Turk" Turkowski)
Newsgroups: comp.lang.c++
Subject: Re: operator[] for 2D array class
Message-ID: <5890@internal.Apple.COM>
Date: 20 Dec 89 05:30:08 GMT
References: <21162@ut-emx.UUCP>
Organization: Advanced Technology Graphics, Apple Computer, Cupertino, CA, USA
Lines: 31

In article <21162@ut-emx.UUCP> ycy@walt.cc.utexas.edu (Joseph Yip) writes:
>I am working on some routines that manipulate 2D array. In order to
>access individual elements, I define a operator [] member function.
>However, operator [] only takes one parameter. In order to do
>	A[i][j] = B[i][j]	// A and B are two 2D array classes
>I do:
>Tmp Array2D::operator [] (int i) {
>	...
>}
>
>int& Tmp::operator[] (int j) {
>	...
>}
>
>In this way, the problem is solved. 
>Is there any better way to do this object array indexing?
Yes; e.g.

	class 2DarrayOfElements {
	private:
		int nCols;
		element *M;
	public:
		element* operator [] (int i) { return(M + i * nCols); }
	};

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Ken Turkowski @ Apple Computer, Inc., Cupertino, CA
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