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: iaXeqfIrYKxPJRXxfSm, rIYKxPJRXxfsjVsqe

Answer: YKxPJRXxf


Question: mCxQTIaXN, mWQTIaxzPT

Answer: QTIa


Question: zGAkrCdTitZiIzuRk, vrwQsmWdTitZiIXy

Answer:
dTitZiI