in your original you have this:

foreach$h(split//,"JussJsstssPerlJssjsssssPsjusjsssuerpjsjsssusjpersjulJllsjJ" (etc).

So the char that you're matching (which you change into a number based on its position within the jsreutPJpl string) is in $h

What i did was replace the foreach loop with a regex:
$_=<long string here>;s^.^<the code from the foreach loop here>^eg

So now instead of in $h the character from the long string, which is being matched is in $&.

so what this: $_="jsreutPJpl";s/$&/$p=pos/e; does is find the char from the long string within the short string.

pos returns to position of the match within the short string. set $p to this and return it into the long string regex substitution - so now in the long string each character has been replaced by it's position in the short string - ready for adding dots...

hth.
alex