The code itself is okay, except that that arrays 3 and 4 do not contain a non-overlapping set of substrings of the string they are operating on and will therefore not meet the substitution criteria later in the program. To get the desired result:
my @a3 = qw( CCACCAGCACC );
my @a4 = qw( CCAACACC );

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In reply to Re: Bracketing Substring(s) in the String by anonymized user 468275
in thread Bracketing Substring(s) in the String by monkfan

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