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: kUoqCMPFTqGE, guoqCMPkwJs

Answer: oqCMP


Question: LudFxiaqbX, UWMPnFxiaqikiDx

Answer: Fxiaq


Question: TVtkWb, fztkwW

Answer:
tk