From:	j DOT aldrich6 AT genie DOT com
Message-Id:	<199604040625.AA102929134@relay1.geis.com>
Date:	Thu, 4 Apr 96 05:57:00 UTC 0000
To:	calvid AT rpi DOT edu
Cc:	djgpp AT delorie DOT com
Mime-Version:	1.0
Subject:	Re:Why doesn't this code work?

Reply to message 8964006    from CALVID AT RPI DOT ED on 04/01/96  4:59PM


>	for(i=0; i<50; i++)
>		for(j=0; j<50; j++)
>			array1[i][j] = 0;
>
>	array2[0] = 1;
>	array2[1] = 2;
>	cout << array2[(array1[i][j])] << endl;

At the end of your for loops, i and j are each 50.  This is out of the bounds
of array1, which is subscripted [0..49][0..49].  Remember that array
subscripts begin with zero!  As a result, the value the program finds at
array1[50][50] is a random piece of garbage in your memory somewhere,
which will almost certainly cause unexpected results when used as a
subscript of array2!  The reason DJGPP gives you SIGSEGV is that it is
much more particular about what areas of memory you access than is
Linux.

I you really want to initialize the array to zero on startup, why not just
declare
it static?

John

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