use strict;
print "Shifting all words into letter data files - ";
open(DATA,"all.txt") || die "cannot open all.txt for input: $!";
while(<DATA>) {
	my $word = $_;
	chomp($word);
	$word=~s/^\s+//;
	my $letter = lc(substr($word,0,1));
	if($letter!~/[a-z]/) {
		$letter = "___";
	}
	if(-e "$letter.dat") {
		open(FILE,">>$letter.dat") || die "cannot $letter.dat for append: $!";
	} else{
		open(FILE,">$letter.dat") || die "cannot $letter.dat for output: $!";
	}
	print FILE "$word\n";
	close(FILE);
}
close(DATA);
print "done\n";

print "Organizing letter file alphabetically - \n";
open(DATA,">all1.txt") || die "cannot do $!";
foreach my $filename (sort {lc($a) cmp lc($b)} <*.dat>) {
	print "\topening $filename - ";
	my @words = ();
	open(FILE,$filename) || die "cannot do $!";
	while(<FILE>) {
		my $word = $_;
		chomp($word);
		push(@words,$word);
	}
	close(FILE);
	print "\t\tsorting - ";
	@words = sort {lc($a) cmp lc($b)} @words;
	print "done\n";
	print "\t\tremoving duplicated - ";
	my $prev = "not equal to $words[0]";
	@words = grep($_ ne $prev && ($prev = $_, 1), @words);
	print "done\n";
	foreach my $word (@words) {
		print DATA "$word\n";
	}
	print "\tdone\n";
}
print "done\n";