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: zqRbqwgmqGIAGTeeoGFOSr, RFnLqwgmqGIAGLcEvAWxY

Answer: qwgmqGIAG


Question: nFgMXUzpStDAybiwm, aNJrXUzpStDjp

Answer: XUzpStD


Question: MeVhBIOBvLvYftVjyG, mtaAbiAJIOBvLvYftVLO

Answer:
IOBvLvYftV