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: UtUSmsOI, dCUSmGoQ

Answer: USm


Question: eedZoMwKgDhdsgs, kMMwKgDLm

Answer: MwKgD


Question: IMhBSmurDVRv, UggySmurDTOhpD

Answer:
SmurD