my $num_chars = 0;
<>;
while ( <> ) {
    do {print "$num_chars\n"; $num_chars = 0; next} if /^>/;
    $num_chars += tr/ACGT/ACGT/;
}
print "$num_chars\n";

##</code><code>##

my @num_chars = ();
my $i = -1;
while ( <> ) {
    $i++, next if /^>/;
    $num_chars[$i] += tr/ACGT/ACGT/;
}
foreach ( @num_chars ) {
    print "$_\n";
}