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: FCKbAgSVgj, wAEAWbAgSVSVwD

Answer: bAgSV


Question: zqRbqwgmqGIAGTeeoGFOSr, RFnLqwgmqGIAGLcEvAWxY

Answer: qwgmqGIAG


Question: WJpWMFTJUlMNwcHYXXWd, bTVwRoIMFTJUlMNyUgbI

Answer:
MFTJUlMN