You were close. This will do what you intended. 
$string='abchijk';
while ($string =~ s/(\w{2})(\w)/$1\|$2/) {
    print "$string\n";
}

[download]
When you were using (.*) it was matching the '|'

John

In reply to Re: regex multiple times by Cyrnus
in thread regex multiple times by Anonymous Monk

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