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

Answer: SEm


Question: XZslQqrShfCXRXyHrFVq, BtOQgQqrShfCXRRCRbMvXPM

Answer: QqrShfCXR


Question: DBnGdblIdrRGTBs, xVzscprGdblIdrsHO

Answer:
GdblIdr