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: eeoJEtGHPDvHck, ezPGHPDvHSf

Answer: GHPDvH


Question: ZGkBNEDRAwURXnxBIOJkzTvg, HMAwURXnxBMfGbPOBf

Answer: AwURXnxB


Question: gYTsJOCqFEcAoCDRsknUSpp, qDqFEcAoCDxrNMk

Answer:
qFEcAoCD