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: nFgMXUzpStDAybiwm, aNJrXUzpStDjp

Answer: XUzpStD


Question: VGRjWGHRcBdFmkVg, eSwqALQXWGHRcBdFsDXCM

Answer: WGHRcBdF


Question: WjUicPWbMDWJDTAUEHOxM, KBkAMgPWbMDWJDKUuIxyyI

Answer:
PWbMDWJD