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my @b=map { 
    my $mapkey=$_; 
...
          ? [@{$d[$mapkey]}] : ()
    } 0..$#a 
} 0..$#d;

my @b = map {
  my $d = $_;
  map { ($d->[1] =~ $$_) ? $d : () } @a
} @d

my %a = map { $_ => 1 } @a;
my @b = map {
  ($a{$_->[1]}) ? $_ : ()
} @d