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

Q: mCxQTIaXN, mWQTIaxzPT

A: QTIa
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Q: hUpEbyvEcQ, dHpEbyvEvwsXcN

A: pEbyvE
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Q: klqVzFnyxFMUEtEmZJc, wSiFnyxFMUEtEDEgSJbVNbM

A:
FnyxFMUEtE
****