From: George Foot <mert0407 AT sable DOT ox DOT ac DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro ex11.c
Date: 9 Feb 1998 22:17:03 GMT
Organization: Oxford University, England
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On Mon, 09 Feb 1998 13:18:12 -0800 in comp.os.msdos.djgpp Dan
<dyoon AT home DOT com> wrote:

:       hotspot[c] += (random() & 7) - 3;

: what does "random() & 7" do?  i'm figuring random() returns a random
: # of type int maybe?  but i have no idea what the "& 7" does.  the & 7
: is the only thing that i need an explenation for.  any help would be
: much appreciated.

`&' is the bitwise AND operator.  If you don't know what this means, I
suggest you read about boolean operators in a C book.

In this case, `random' returns an integer.  ANDing this with 7 results
in a number from 0 to 7; subtracting three gives a number from -3 to 4.

-- 
george DOT foot AT merton DOT oxford DOT ac DOT uk

ko tavla fo la lojban