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

Answer: GPQVPrqP


Question: PGjDRPDzGaBR, rpIJRPDzWi

Answer: RPDz


Question: laYYsiLFxBzZxZKTyYY, ufmKgPFFxBzZxZKYHmt

Answer:
FxBzZxZK