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: tGBRASi, QABRAtL

Answer: BRA


Question: MSzHyOuaJILkeY, eUibEHoHyOuaJIhfvXy

Answer: HyOuaJI


Question: RepkPhekvWEWuGrW, MAPekvWEWuGtIjmpuID

Answer:
ekvWEWuG