use Table::ParentChild;
use File::Slurp;

my @relationships;
my $i=0;
foreach my $line (read_file("data"))
{
  my ($child, $parent)= split ' ',$line;
  $relationships[$i++]= [$parent, $child];
}

my $table = new Table::ParentChild( \@relationships );

my $child= 1045316419;
while (my @parents = $table->parent_lookup( $child ))
{
  print "Parent of $child is ", $parents[0],"\n";
  $child= $parents[0];
}