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

Q: HorIyjpfBFmKZQUIEoP, AcWOaOgVPmyjpfBFmKZQPFYiI

A: yjpfBFmKZQ
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Q: PGjDRPDzGaBR, rpIJRPDzWi

A: RPDz
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Q: BlCNTtegvlQvvzBgSGLTstN, bSdQvvzBgSGLTHERg

A:
QvvzBgSGLT
****