#!/usr/bin/perl
# 
# Requirements:
# 1) Provide a stand alone Perl program that eficiently stores lines occuring in 
#       $shortfile, but not in $longfile, into $differences. 
#
# dupslib.pm contains subroutines to provide input content and consume the output.
#
#	by Chris Yager
#   (c) 2005 
############################################################

use strict;
use warnings;
use dupslib;       ## library to fill scalers & output the $differences.

my $shortfile;
my $longfile;
my $differences = "";
my %myhash = ();

($shortfile, $longfile) = fill_scalers();		# get input.

# put $longfile into a hash.
	my @lines = split("\n", $longfile);		# split into lines.
	foreach my $line (@lines) {				# for each line in lines.
		$myhash{$line}=1;					# 	use line as hash key.
	}

# find lines of $shortfile in the hash.
	my @strs = split("\n", $shortfile);					# split into lines.
	foreach my $str (@strs) {							# for each line in lines.
		if	 (exists $myhash{$str})						# test existence of key. 
			 { }										# do nothing (already exists). 
		else {$differences = $differences."$str\n"};	# append to $differences. 
	}
	
# These 2 lines do the same as the 2 groups of lines above.
#	map $myhash{$_}=1, split(/\n/,$longfile);							# make hash.
#	map {$differences.=exists $myhash{$_}?'':"$_\n"} split(/\n/,$shortfile);	# find.

save_results($differences);			# do something with the results.
exit;