#!/usr/bin/perl
#use strict;
use warnings;

$numArgs = $#ARGV + 1;

if ($numArgs < 2)
{
	print "USAGE: extract_duplicate_rows <input file> <# of duplicate rows>\n\n";
	exit(0);
}

$finput = $ARGV[0];
$duplicate_count = $ARGV[1];


open(IFILE, "<", $finput) or die $!;

chomp($prev_line = <IFILE>); 
$match_count = 1;

while (1)
{
	chomp($line = <IFILE>); 
	
	if ($line eq $prev_line)
	{
		$match_count++;
	}
	else
	{
		if ($match_count == $duplicate_count)
		{	
			print "$prev_line\n";
		}

		$prev_line = $line;
		$match_count = 1;

		if (eof(IFILE))
		{
			last;
		}		
	}
}

	
close IFILE;