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: ykDpbd, YFDpmO

Answer: Dp


Question: cxYVucnmEQopeWHrPJ, jNnOaYVucnmEQoSE

Answer: YVucnmEQo


Question: gIRDCw, ZTRDyO

Answer:
RD