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

Q: yRhCObvPZYoKUoQnyaatR, NHzLJYPZYoKUoQnJnIsZxC

A: PZYoKUoQn
****
Q: AxRSlkQfWHrdlgQG, iXIOrmlkQfWHTy

A: lkQfWH
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Q: PGwQeJQRRhDRxeKohG, uyLeJQRRhDRxIwNTonSip

A:
eJQRRhDRx
****