#!/usr/bin/perl -w
use strict;

print doFunc( "AABBCC",0 );  
print doFunc( "AAAABBBBCCCC",0 );  

 sub doFunc
 {
   my( $theParam,$depth) = @_;
print STDERR "dofunc($theParam)\n";
   my $re;
   $re = ${['(.+)\1']}[$depth]||'(.+)(\1)';

print STDERR join"\n", $theParam =~ /$re/g,'';
   $theParam =~ s/$re/&doFunc($1,$depth+1)/ge;

    ++$theParam;
print STDERR "=$theParam\n";
   return $theParam;
}