open(D1,"<d1.sorted");
open(D2,"<d2.sorted");

my $d1 = "v1 v2 v3";
my $d2 = "t1 t2 t3";
my ($d1k,$d2k)=('','');

for(;;) {
  my $c = $d1k cmp $d2k
    or print join(" ", split(/\s+/,$d1), (split(/\s+/, $d2))[2]),"\n";

  if ($c <= 0) {
    last unless defined($d1 = <D1>);
    $d1k = ($d1 =~ /^(\d+\s+\d+)/)[0];
  }

  if ($c >= 0) {
    last unless defined($d2 = <D2>);
    $d2k = ($d2 =~ /^(\d+\s+\d+)/)[0];
  }
}