#!/usr/bin/perl

srand();	# initiate random generator for rand() command
$totalline = 0;	# var for hold total number of lines (names); starts it at 0

if (!$ARGV[0] || !$ARGV[1]) {
	&usage;
} else {
	&openread;
	&compile_list;
	&makegroups;
}

# Usage Subroutine.  Displayed if program not used properly
sub usage {
	print "Random Couple Generator\n";
	print "\n Usage \n";
	print "./random-couples.pl name-file target-file\n";
	print "Example:  ./random-couples friends couples\n";
	print "\t Where friends is your list of friends, 
		and couples is the new list of couples\n\n";
}

# opens specifed read file, and processes it to be parsed
sub openread {
	open (READ, "< $ARGV[0]") or die "Cant open $ARGV[0] : $!";
	while(<READ>) {
		s/#.*//;		# ignore comments (remove them)
		next if /^(\s)*$/;	# skip blank lines
		s/\d//g;		# remove any numbers in the text file
		s/\.//g;		# remove periods
		chomp;			# remove newline (\n)
		push @file_contents, $_;# push line into array
	}
}

# calculates how many lines are in the file
sub randomize {
	while (@file_contents) {
		$totalline++;		# find total number of names
	}
}

# create array with random names
sub compile_list {
	foreach $names (@file_contents) {
		&randomize;					# find total number of names
		$ng = int(rand($totalline));			# random number from 0 to $totalline, made into an integer for array
		$finalizedlist[$tmp] = $file_contents[$ng];	# set finalizedlist element $tmp to random number
		splice(@file_contents, $ng, $ng);		# take person out
		$tmp++						# goto next value of finalizedlist array
	}
}

# open write file, write two random people, close write file
sub makegroups {
	$fark = 0;
	$fark2 = $fark + 1;
	while ($fark2 != $totalline) {
		open (WRITE, ">> $ARGV[1]") or die "Can\'t open $ARGV[1] : $!";
		print WRITE "Group $fark: ".$finalizedlist[$fark]." and ".$finalizedlist[$fark2]." are partners\n";
		close WRITE;
		$fark++;
		$fark2 = $fark + 1;
	}
}

##</code><code>##

1.bobby
2.jane
3.charleen
4.markus
5.gabriel
6.Alex

##</code><code>##

Group 0: Alex and  are partners
Group 1:  and  are partners
Group 2:  and  are partners
Group 3:  and bobby are partners
Group 4: bobby and  are partners
Group 5:  and  are partners
and then it goes like Group 5, until it reaches 24.