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: STvKOHq, XMGvKOdyM

Answer: vKO


Question: FNVeaFmprNHqqtAaKv, iGBmrrMveaFmprNHqWWAvtht

Answer: eaFmprNHq


Question: guUJshwOYMDCkCaaIRN, tAfWZxGwJshwOYMDCPfAi

Answer:
JshwOYMDC