#!/usr/bin/perl<br>

use strict; 
use warnings;

use List::Permutor;


my $OutFile = '>permutations.txt';
open(OUTFILE, $OutFile) or die "The file $OutFile could not be found.\n";

my $word = 'aabc';
my $perm = new List::Permutor split(//,$word);

while  (my @set = $perm->next) {
	#print @set
 	for(my $i=0; $i<length($word)-1; $i=$i+1) {
 		my $letter = $set[$i];
 		print OUTFILE "$letter,";
 	};
 	my $letter = $set[length($word)-1];
 	print OUTFILE "$letter\n";
}
close (OUTFILE);

##</code><code>##


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

chdir('//Users/laptop/Desktop/') or die ("Sorry could not change to the perl/programs directory.\n");

my $AllPermutations = 'permutations.txt'; #INFILE
open(ALLPERMUTATIONS, $AllPermutations) or die "File: $AllPermutations failed to open: $!\n";

my $UniqPermutations = '>unique_permutations.txt'; #OUTFILE
open(UNIQPERMUTATIONS, $UniqPermutations) or die "The file $UniqPermutations could not be found.\n";

my @AllPermutations = <ALLPERMUTATIONS>;

my %seen = ();
my @unique = grep { ! $seen{ $_ }++ } @AllPermutations;

print "@unique";
my $str = "@unique";
print join(",",split(//,$str));

close(ALLPERMUTATIONS);
close(UNIQPERMUTATIONS);