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: QlJnxO, BLJnCQ

Answer: Jn


Question: wYhGWdRC, cFGWdHEy

Answer: GWd


Question: GUWXVvBKwKNbobhQGejGyEAT, VkLdKwKNbobhQGAWDjamN

Answer:
KwKNbobhQG