Ok, let me try again with some examples of how data look now (old) and should look (new):
-case 1: only 's' 
old:sssss
new:iiiii

[download]

-case 2: only 's' and 'U' 
old:sssUUss
new:iiiMMoo

[download]

-case 3: only 's' and 'D' 
old:sssDDss
new:oooMMii

[download]

-case 4: 's', 'D' and 'U' (all possible characters) 
old:sssssDDDDDDDssssUUUss
new:oooooMMMMMMMiiiiMMMoo

[download]

OR 
old:sssssUUUUUUUssssDDDss
new:iiiiiMMMMMMMooooMMMii

[download]

For some reason, the code I wrote changes many but not all cases... Not that you cannot see s+D+s+D+s+<code> sequence, or <code>s+U+s+U+s+<code>. <code>D and U alternate.

In reply to Re^4: Pattern matching simultaneous substitution by Anonymous Monk
in thread Pattern matching simultaneous substitution by Anonymous Monk

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