use strict;
use Graph;
use Graph::Undirected;

my $ud = Graph::Undirected->new();

while(<DATA>)
{
  my @items = split(' ');
  if(@items <= 1)
  {
    $ud->add_vertex(@items);
  }
  else
  {
    $ud->add_path(@items);
  }
}

foreach my $connectedSet ($ud->strongly_connected_components)
{
  print "Connected Nodes: " . join(',', @$connectedSet) . "\n";
}

__DATA__
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