A couple of map statements should make this pretty easy to do with an array:

my @array = map { chomp and $_ } <DATA>;

my $want = 'Julia_Roberts';
my $change = 'Cintheia';

my ( $suffix ) = map { m/\A$want(\(\S+\))\z/smx and $1 } @array;
my @final = map { ( /\A($change)\z/ and "$change$suffix" ) or $_ } @ar
+ray if $suffix;

warn Dumper \@final;

__DATA__
Julia_Roberts(1,5)
Cintheia
Chelsia
Rohan
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The first map statement goes through the array and identifies the suffix for the pattern to be matched and the second applies the suffix to the desired element. I would probably do some kind of error checking after the first map, getting an array instead of a scalar from the map and checking to see if there's only one element returned -- what do you do if Julia_Roberts(1,5) and Julia_Roberts(2.8) are in the list?

perl -e 'split//,q{john hurl, pest caretaker}and(map{print @_[$_]}(joi
+n(q{},map{sprintf(qq{%010u},$_)}(2**2*307*4993,5*101*641*5261,7*59*79
+*36997,13*17*71*45131,3**2*67*89*167*181))=~/\d{2}/g));'
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