The docs: from perlop 
Binary "%" computes the modulus of two numbers.Given integer operands
$a and $b: If $b is positive, then "$a % $b" is $a minus the largest
multiple of $b that is not greater than $a.  If $b is negative then
"$a % $b" is $a minus the smallest multiple of $b that is not less tha
+n
$a (i.e. the result will be less than or equal to zero).  Note that
when "use integer" is in scope "%" gives you direct access to the mod-
ulus operator as implemented by your C compiler.  This operator is not
as well defined for negative operands, but it will execute faster.

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Boris

In reply to Re^3: Find if a number is a multiple of a number. by borisz
in thread Find if a number is a multiple of a number. by Baratski

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