Update:

Per elusion's update, he has already fixed both solutions.

============

Your solution one does not compile.

Your solution two does not work, and it does not print anything:

use strict;
use warnings;

print max(1.23,2.6,55.1,4,5);

sub max {
    my ($max, $next, @vars) = @_;
    return if not $next;
    return max( $max > $next ? $max : $next, @vars );
}
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