Don't use $a and $b :)

use List::Util qw( max );

($a, $b, $c) = (3, 12, 42);

print +(sort { $b <=> $a } $a, $b, $c)[0];
print max ($a, $b, $c);
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These both work, but can you - as a perl beginner - still read it? Perl is so much fun due to TIMTOWTDI