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: UvYbfKFybXofcwLRrLRiK, BgMZKFybXofcVe

Answer: KFybXofc


Question: GrvtMjEvRlmN, ifGOWMjEvRPSOZK

Answer: MjEvR


Question: rFQGvfr, VrQGvWPg

Answer:
QGv