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

Q: CuizrSvJTRWZK, udyrSvJTRZzkS

A: rSvJTR
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Q: kWTQrtCaoTbXIiXDphMG, pLhxkfeDoTbXIiXDpCCzTYyZv

A: oTbXIiXDp
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Q: EmPRBLgdEdqCQkqYw, idODkZIgdEdqCQkHtihrb

A:
gdEdqCQk
****