I have a very specific need and I have just enough knowledge to make me dangerous, but not enough to put that lethality to good use. What I need to do is take a string from one file, file1.txt for example, and remove any shared letters with a string from another file, file2.txt for example. And then do the same for the string in file2.txt.

Sample Input:

File1.txt: CHARLIE ROOT
File2.txt: HARRY NODE
Output: CLI T Y ND

In the above the letters shared between the two strings are removed and the resulting combined string is printed out. I have about 300 lines per file. Can someone help?

In reply to Mostly Harmless by emdub

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