If you have a recent version of List::MoreUtils 

use List::MoreUtils qw( singleton  );
my $str = join '',singleton 
         split '',"abcdefghiaabccdjklm";
print $str;

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poj

In reply to Re: How to remove duplicate characters in a string in place by poj
in thread How to remove duplicate characters in a string in place by punitpawar

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