in reply to Match only certain characters?

It seems to me that you are asking for something as simple as this.

my @ss = (
    'A',
    'B',
    'C',
    'AB',
    'CA',
    'ABC',
    'xABCx',
    'BxCxAx',
);

for my $s (@ss) {
    if ($s =~ /A/ && $s =~ /B/ && $s =~ /C/) {
        print "$s\n";
    }
}

[download]

Which outputs:

ABC
xABCx
BxCxAx

[download]

EDIT: This response is only to the first part of the OP's question. That is:

...if you have the strings:

$a='ABCAAAABBBCCCCCAAABBBCCC';
$b='ASRGRTGRT89579843rrrrrr';

and you wanted to pick only the string that contains A, B and C (namely $a)...

Replies are listed 'Best First'.
Re^2: Match only certain characters?
by AnomalousMonk (Archbishop) on Nov 09, 2009 at 18:18 UTC
    But the OP asked for...
    ... a way to search only for the string that has the letters A,B,C and no other letter ...
    which clearly excludes a string like 'xABCx'.
[reply]
[d/l]

      In that case, I'd have to do this, then.

      my @ss = qw( A B C AB CA ABC xABCx BxCxAx );

for (@ss) {
    if (/A/ && /B/ && /C/ && !/[^ABC]/) {
        print "$_\n";
    }
}

      [download]
[reply]
[d/l]

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