#!/usr/bin/perl -w

@oligos = qw/ AGTCC AGT GTAC AGGAGGAT AGAGG GAGCCCCA CCICC GA /;
@sorted = sort byLength @oligos;

sub byLength {
return (length($a) <=> length($b)); #needs to be $a and $b 
}

print join("\n", @sorted),"\n";