#! /usr/bin/perl -Tw

my ($label, $string);
$string = "a1:  a,b,c";
$string =~ s/\s+//g;  # $string = a1:a,b,c
($label, $string) = split(/:/,$string);
my @tokens = split(/,/,$string);
foreach (@tokens)
{
  print "$_\n";
}