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: KvPFobZEGs, eKFobZEtnm

Answer: FobZE


Question: aIZIsqL, wxSZIsEnO

Answer: ZIs


Question: frXAQKeqxtcuYBrGlGjOqlU, pRxtcuYBrGltevmNsW

Answer:
xtcuYBrGl