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: KJswoapnXz, EQswoaFyH

Answer: swoa


Question: DUhUbmfLuOFAQann, kwnzfLuOFAErR

Answer: fLuOFA


Question: gfXPLNzsyfEotmHL, oJeXPLNzsyJuXP

Answer:
XPLNzsy