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: HSsyZzZLZAAq, MFEZzZLJC

Answer: ZzZL


Question: cUCQXEFSgRZjK, RYdvUQXEFSgRZVlwx

Answer: QXEFSgRZ


Question: oCFfLIiZIanlrQrXA, RHbSJsTBfLIiZIanlrLA

Answer:
fLIiZIanlr