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: CiTNsbepy, DFNsbeZl

Answer: Nsbe


Question: gWMyioGBRpwcXfr, AOQGBRpwcSccqBE

Answer: GBRpwc


Question: KaiLXKUXANqNZMpq, zUTSHKUXANqNMSlNU

Answer:
KUXANqN