Unless your arrays are hugely massive, something like this:

use strict;
use warnings;

my @x = qw/c d e f k l m n/; 
my @y = qw/4 6 5 2 9 7 8 3/;

### Combine arrays for easy sorting
my @z; push @z, [$_, $x[$_], $y[$_]] for 0..$#x;

print "Max values (only 5) in descending order with positions in name 
+array:\n";
print "$_->[2] corresponds to $_->[1] at position $_->[0]\n"
    for (sort { $b->[2] <=> $a->[2] } @z)[0..4];

print "\n";

print "Min values (only 5) in ascending order with positions in name a
+rray:\n";
print "$_->[2] corresponds to $_->[1] at position $_->[0]\n"
    for (sort { $a->[2] <=> $b->[2] } @z)[0..4];
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