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: QEEVsnbQIgrxaZmflaZ, dPSbljkdQIgrxaZmgVzMT

Answer: QIgrxaZm


Question: UtUSmsOI, dCUSmGoQ

Answer: USm


Question: GZIsKsDbDgXAgkbo, GHZvrDbDgXAgkNQYeCUq

Answer:
DbDgXAgk