#!/usr/bin/perl

$|=1;

while (<>) {
  chomp;
  my ($block, $shapes) = split /: /;
  push @{$seen{$shapes}}, $block;
}

for my $k (keys %seen) {
  if (@{$seen{$k}} > 1) {
    print "$k: @{$seen{$k}}\n";
  }
}