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: pqFpUjQGiofBOjfYkRW, pQMnCFlhFpUjQGiofbc

Answer: FpUjQGiof


Question: CxosNa, ikosdx

Answer: os


Question: ksRxEVrz, cOMRxEViwF

Answer:
RxEV