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: iwSQnplQZFbXQ, lHWnplQZFzswgU

Answer: nplQZF


Question: nXVXIEGP, fkXIEkU

Answer: XIE


Question: oKHBuyJnxAZnipdsoWRFs, AgAlvyJnxAZnipvzmzTHkt

Answer:
yJnxAZnip