#!/usr/bin/perl -wn

use strict;

our $want;

BEGIN {
      $want = shift @ARGV;
      die unless $want =~ m/^\d+$/;
}

our $drop;

if (m/^\S/) {
    $drop = 
	m/^2 / ||
	m/^3 \d+ \d+ \d+ (?!$want )\d+ /;
}

next if $drop;

print or die $!;