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: jinzsW, SMnzaW

Answer: nz


Question: yPODMimvyQPYWHfcM, aZiotMimvyQPZncH

Answer: MimvyQP


Question: xppGvlmX, vWxGvlqD

Answer:
Gvl