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: lsNwypFwhKP, diEfLwypFwEKqCN

Answer: wypFw


Question: yOGvgtAmwMwcIRtJ, cQtAmwMwcIRjfjO

Answer: tAmwMwcIR


Question: IIxkBbeiSLn, wqBbeiSAOTF

Answer:
BbeiS