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use strict;
use warnings;

my $expr = $ARGV[0] || die();
my $n = $ARGV[1] || die();
die if ($n < 1) || ($n > length($expr));

$expr =~ tr/[\xc0-\xdf]\xa8/[\xe0-\xff]\xb8/;   # lc
($expr =~ m/^[\xe0-\xff\xb8\-]+$/s) || die();


open(F, 'index') || die("failed to open 'index': $!");
while (<F>)
{
    chomp();
    print "$_\n" if (match($_, $expr, $n));
}
close(F);


sub match
{
    my ($str, $expr, $n) = @_;

    return if length($str) != $n;
    foreach my $letter (split(//, $str))
    {
        my $pos = index($expr, $letter);
        return if ($pos < 0);
        substr($expr, $pos, 1, '');
    }

    return 1;
}