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: jeQzwP, kSQzxq

Answer: Qz


Question: JXnHYuZvAYK, zhUYuZvASGhd

Answer: YuZvA


Question: rfgaSHBwOyeXcoDhJzPj, sXaBEivWjSHBwOyeXcAooSHb

Answer:
SHBwOyeXc