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: yjoJzBGdwfOhsceoOpoap, uSLMdBGdwfOhsIQHBijd

Answer: BGdwfOhs


Question: fREVIdeTcakgFnwDWTVev, IbtXImseeTcakgFnwDYsKBAlux

Answer: eTcakgFnwD


Question: VsmKDRaXXFnGlbxhgImQuHr, XFKymXFnGlbxhEzXCQpvU

Answer:
XFnGlbxh