push @{$count{$chr}{$loc}}, $seq;
    #++$count{$chr}{$loc};
...
    return exists $count{$chr}{$loc} ? scalar @{$count{$chr}{$loc}} : 0;
    #return exists $count{$chr}{$loc} ? $count{$chr}{$loc} : 0;
...
            print "Reads on CHR:$chr LOC:$loc = ", scalar @{$count{$chr}{$loc}};
            #print "Reads on CHR:$chr LOC:$loc = ", $count{$chr}{$loc};