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: njzfcapS, JDzfcYQh

Answer: zfc


Question: pySBCdpe, AEBCdOR

Answer: BCd


Question: mrSEOuPwao, nmoySEOuPIWx

Answer:
SEOuP