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: YPeBvuJXaSLLPhKpUQ, ryjPdyuJXaSLLPhIzBeJP

Answer: uJXaSLLPh


Question: rPPfxUdowLLdvwRtY, PuHovApkfxUdowLLBOhq

Answer: fxUdowLL


Question: XZslQqrShfCXRXyHrFVq, BtOQgQqrShfCXRRCRbMvXPM

Answer:
QqrShfCXR