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

Q: jLbHvZmecfxMcGLXGVsO, erFBGmecfxMcJtDyKGZ

A: mecfxMc
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Q: nuwMzarLqoPvabJla, JKcrLqoPvabJNDCILGQ

A: rLqoPvabJ
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Q: YsbTRVYqvaNak, qBMRRVYqvaFm

A:
RVYqva
****