Friends,
I have encountered one problem for the below input because the last character G of first line and the first character C of the next line are @allowed region. But when I get the output, G and C are not in @allowed. This is because in the input there is a space after the last character G and the character C is in the next line. 

my @allowed = qw[ AA AG GC GT CA CG TT TC ];
my $allowed = join "|", @allowed;
my $regex   = qr/ N+ | (?: (?=$allowed) . )*  . /x;

$data="TGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG
+GGGGGGGGGGGGGGGGGGGGGATAG
C";
print "$_\n" for $data =~ m/$regex/g;

[download]

ie instead to be printed as GC, I get it as 

G
C

[download]

which is wrong

Please give a solution.

2005-10-21 Retitled by planetscape, as per Monastery guidelines
Original title: 'Reading Substring'

In reply to How to remove Newline by Benson

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