But BrowserUk's approach will work for any two strings (Update: assuming, as GrandFather points out, that the two strings are identical except for the Xs), while your solution depends on the particular structure of the strings given in the example of the OP.

In reply to Re^2: Replacing letters in one string based on another by AnomalousMonk
in thread Replacing letters in one string based on another by wallacei

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