In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Q: xeKSiBafhOWBbYwlGaQ, GUfIsKgafhOWBbYiFWnptAt

A: afhOWBbY
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Q: yRhCObvPZYoKUoQnyaatR, NHzLJYPZYoKUoQnJnIsZxC

A: PZYoKUoQn
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Q: CQWVytLkqHnWUAxt, cKytLkqHnWGOXcmLa

A:
ytLkqHnW
****