This is how I thought I can negate a number:
$p = 7;
$n = -$p;        # or 0 - $p
print $n;        # -7
printf "%x", $n; # FFFFFFF9

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But in the document i'm reading, it says to negate the number, and the example says the result of negating 0x0007 is FFF8. I looked on the web, and found someone gave an example of negating a number (in another programming lang) by XOR-ing the number with 0xFF:
$p = 7;
$n = $p ^ 0xFFFF_FFFF; # im on 32-bit winxp system
printf "%x", $n; # FFFFFFF8

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So, im confused, what's right?

In reply to Negating a number by flamey

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