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: xQcYRVFFqrVAMsBm, VErcKZvcYRVFFqzKo

Answer: cYRVFFq


Question: HiEuutntEBpU, fdkqEuutntEBABdGZRND

Answer: EuutntEB


Question: MrRPUO, epRPga

Answer:
RP