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: oHoJrr, YAoJSq

Answer: oJ


Question: PnRypl, HvRydi

Answer: Ry


Question: guWVDgKRxSGp, bRzBeVDgKRmfSi

Answer:
VDgKR