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: nxTtNYaazlOyEBApiUSJS, BLazlOyEBCV

Answer: azlOyEB


Question: ljwjMioOwfOltGBaE, TneNGsoOwfOlxnWWW

Answer: oOwfOl


Question: JqHhvf, TJHhEG

Answer:
Hh