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: CdRbREFMEDTXnEzgn, zHLEMMEDTXnEPH

Answer: MEDTXnE


Question: yQRDycTycwH, ImycTycrR

Answer: ycTyc


Question: jSXZBTKdUKXMqyaDyftLx, kuSwBdcWwKXMqyaDyfLsawMoi

Answer:
KXMqyaDyf