I need a function (call it 'fix' for lack of a better name) to find the value $N that is an even multiple of $m that is larger than or equal to $n. (See note at bottom for clarification of "even multiple") The best I came up with requires control flow logic and I was wondering if anyone could suggest something better, preferably that doesn't require an 'if'. 

sub fix{
    my ($n,$m)=@_;
    my $M = $n % $m;
    $M ? $n + $m - $M : $n
}

print "<table width='80%' align='center' border='1'>\n";
print "<tr><th></th><th colspan='4'>\$m</th></tr>\n";
for my $n (0..20) {
    print "  <tr>".join("", map { "<th>$_</th>" } '$n',2..5),"</tr>\n"
        unless $n;
    print "  <tr>".join("", map { "<td>$_</td>" } $n,map fix($n,$_),2.
+.5),"</tr>\n";
}
print "</table>";
__END__

[download]
(Sample output below:)
 $m
$n2345
00000
12345
22345
34345
44645
56685
666810
789810
889810
91091210
1010121210
1112121215
1212121215
1314151615
1414151615
1516151615
1616181620
1718182020
1818182020
1920212020
2020212020

Note that $m and $n may be any non negative integer,( and thus be odd, or even prime), so you can't use binary operators like '&'.


---
demerphq

    First they ignore you, then they laugh at you, then they fight you, then you win.
    -- Gandhi

    Flux8

• Update:  
To clarify the use of 'evenly' in the above I mean the definition X divides Y evenly if and only if Y % X == 0. Or expressed another way, Y is an even multiple of X if and only if Y % X == 0. Sorry, I'm not much of a mathematician so I forget the textbook definitions and terms for these things.


In reply to Best way to make sure a number is an even multiple of another? by demerphq

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