my $key = $1;

##</code><code>##

 
my $key = NFD($1); # or NFC, or even NFKD/NFKC

##</code><code>##

foreach my $letter (@letters) {
	my $norm_letter = NFD($letter); 
	my @features = @{ $hash{$norm_letter} };
	print join " ", @features;
	print "\n";
}

##</code><code>##

use Unicode::Normalize;

binmode(STDOUT, ':encoding(UTF-8)');

open HASH, '<:encoding(UTF-8)', 'test_hash.txt';
my %hash = ();
while (my $line=<HASH>) {
	chomp $line;
	$line =~ s/^(.*?)\t//;
	my $key = NFD($1); 
	my @line = split /\s+/, $line;
	$hash{$key} = \@line;
}
# foreach my $phoneme (keys %hash) {
#     print $phoneme . ":";
#     my @line = @{ $hash{$phoneme} };
#     print join ",", @line;
#     print "\n";
# }

open INPUTFILE, '<:encoding(UTF-8)', 'test_input.txt';
while (my $entry = <INPUTFILE>) {
	chomp $entry;
	print $entry . "\n";

	my @letters = $entry =~ /(\X)/g;

	foreach my $letter (@letters) {
		my $norm_letter = NFD($letter); 
		my @features = @{ $hash{$norm_letter} };
		print join " ", @features;
		print "\n";
	}
}