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: YXsgPE, ENsgSO

Answer: sg


Question: lPhVhAQZWJDrvzcEaGEwKgZAuJI, qIJDrvzcEaGDRCRrB

Answer: JDrvzcEaG


Question: JTudLeLuJHlAzECutO, jJgyeudLeLuJHIgBKAc

Answer:
udLeLuJH