while(<>){
        chomp;
        my @s = split /\t/;
        my $r_name = $s[0];
        my $seq = substr $s[9], 0, 12;
        $read2seq{$r_name}{$seq}++;
        
}

my @keys_with_2_unique_vals =
	grep 2 == keys %{$read2seq{$_}}, keys %read2seq;

##</code><code>##

my @keys_with_equal_pair_of_vals =
	grep 1 == keys %{$read2seq{$_}}, keys %read2seq;