At 224 returns general weight, different pearl weight and index of under/over weight pearl as an array. Runs under strict. Unfortunately if your first two groups of 4 pearls do not weigh the same you need 4 goes...oh well who needs a head.

use strict;
my @pearls = (1,1,1,1,1,1,1,1,1,1,2,1);
$, = ",  ";
print perl(@pearls);

#234567890123456789012345678901234567890123456789012345678901234567890
sub perl {
sub w{$"='+';eval"@_"}my@p=@_;@p=w(@p[0..3])==w(@p[4..7])?@p[8..11,0]:
w(@p[0..3])==w(@p[8..11])?@p[4..8]:@p[0..4];$a=pop@p;@p=w(@p[0,1])==$a
*2?@p[2,3]:@p[0,1];@p=(@p[0]==$a)?@p[1]:@p[0];map{$b=$_[$_]!=$a?$_:$b}
0..11;$a,@p,$b
}
[download]

cheers

tachyon

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