Yes--I do understand, and your code works perfectly well for that initial case. Then the OP shows the following case:

my $string1="ABCDE";
my $string2="BBBBB";

[download]

Had the OP used $string2="FFFFF";, your code would not show "F", even though--after a string comparison--"F" is unique to $string2.

I see many good minds working on this issue with different POVs. Again, I think it evidences that the specs are equivocal.

BTW - I didn't downvote yours or others' similar interpretation of "unique;" I merely commented on it.

In reply to Re^6: compare two strings and return only he unique values. by Kenosis
in thread compare two strings and return only he unique values. by Learnlot1

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