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: IVnbnqBqdPcXfHotUzCYoaGQy, PAlyypBRRBqdPcXfHotpZs

Answer: BqdPcXfHot


Question: fVEFJa, WtEFYK

Answer: EF


Question: JZaiCQnFIyxf, KzwaiCQnFXrT

Answer:
aiCQnF