I don't trust modulo on a negative number. I'm never sure what value -2 % 5 will have. 3 or -2? I believe it depends on the language.

So, I want an easy, reliable way to add a multiple ($i) of $m so that $i - $n >= 0. The exact number doesn't matter, as 

   ($r*$m + $s) % $m == $s % $m

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for any non-negative integers $r and $s, and positive integer $m.

$m*$n is both a multiple of $m, and at least as large as $n.

In reply to Re^3: Best way to make sure a number is an even multiple of another? by bart
in thread Best way to make sure a number is an even multiple of another? by demerphq

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