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: oCtWZYdkvZ, pkktWZYdEHMW

Answer: tWZYd


Question: YPeBvuJXaSLLPhKpUQ, ryjPdyuJXaSLLPhIzBeJP

Answer: uJXaSLLPh


Question: IgEBAJvWtZYbYOoNc, UjpvWtZYbYphgF

Answer:
vWtZYbY