In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Q: ugDpSMRvHM, DDwSMRvxw

A: SMRv
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Q: aiqZheFuLtXAGRCGNBTAX, ssnVdztXAGRCGNBTIqmSJLZcy

A: tXAGRCGNBT
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Q: jlxekUWzGtcpcucPvZzgV, ehSYKzGtcpcucPKlz

A:
zGtcpcucP
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