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: ugDpSMRvHM, DDwSMRvxw

Answer: SMRv


Question: RAmKlEAUfWcgF, ZlWfEAUfWvVRa

Answer: EAUfW


Question: LIdKngBVwss, NvCdKngBVpMiKk

Answer:
dKngBV