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: eNuawupVqQ, RIawuplUIf

Answer: awup


Question: fWJdaAfOCfejXZvidHM, gOpfOCfejXZbtLvSLZI

Answer: fOCfejXZ


Question: KKHUkHqlU, mFiaUkHqMAvb

Answer:
UkHq