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: XeQwOS, OuQwNR

Answer: Qw


Question: IzwlZDJSEFPxfIud, xwWSYwlZDJSEFPbvSXTlS

Answer: wlZDJSEFP


Question: yuQVNECGBgZIJO, lmlPNECGBgRYKJJ

Answer:
NECGBg