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

Q: vJtmxQmHEq, yobgAtmxQmMeoLz

A: tmxQm
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Q: aZcGMvzBhazkCIFqpVe, AOljBvzBhazkWXeTuA

A: vzBhazk
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Q: CaJLfgXBqLMNvCpMAIWTL, pZMITCPNXBqLMNvCsxu

A:
XBqLMNvC
****