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: JIOKyo, oPOKsX

Answer: OK


Question: bUcuzFgsdfojVR, IdcuzFgsdMRgtMA

Answer: cuzFgsd


Question: cGgpuCjaWbmFxdbb, YxpuCjaWbnuwa

Answer:
puCjaWb


