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: DQVkAbWTTPhoBx, TeWTTPhonxcIKL

Answer: WTTPho


Question: mvIvSzMtYsfVLdaGEmef, wnzMtYsfVLdaKm

Answer: zMtYsfVLda


Question: aXzFHbmOouA, MrhuRFHbmORtw

Answer:
FHbmO