my @x = qw"q s t l y a p c f v i r d w k o j b";

##</code><code>##

my @p = sort { $x[$a] cmp $x[$b] } 0 .. @x-1;

##</code><code>##

my $d = 0; my @s; 
for my $s (0 .. @p - 1) { 
    if ($s[$s]) { $d++; } 
    for (my $t = $s; !$s[$t]++; $t = $p[$t]) {} 
} 
if (0 != $d%2) 
    { say "odd" } else { say "even" }

##</code><code>##

use File::Temp "tempfile"; 
my($T, $N) = tempfile("perm-XXXXXXXX", UNLINK => 1); 
say $T "SignPerm(PermList(1+[", join(",", @p), "]));\n"; 
close $T or die; 
my $s = qx"gap -q <$N"; 
if (1 == $s) { say "even" } elsif (-1 == $s) { say "odd" } else { die }