Without comparison operators?

#!perl
use strict;
use warnings;

my $vector = (1,23, 3, 2.0**37, -1.0 * 10 ** (-41), 10.0**19);
my $max;
$max = $vector[0];

$max = $_ if $max > $_ foreach (@vector[1..$#vector]);

print "$max\n";
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You'll be comparing them implicitly with a call to a routine like

$max = max (@vector);
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So the literal answer to your question is "no" you can't find the number with the largest or smallest value of a group of values without comparison operators. You can, however, hide the comparison operators in a function.