#!/usr/bin/perl

use warnings;
use strict;

$\ = $/;

$_ = reverse "(a+b)*c"; # or some longer sequence

s/\)([^()]+)\(/]$1[/g;

print scalar reverse y/][/)(/r;

__END__

$ perl test.pl
Missing right curly or square bracket at test.pl line 10, within string
syntax error at test.pl line 10, at EOF
Execution of test.pl aborted due to compilation errors.