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: fdxgzAMP, xrcxgzYW

Answer: xgz


Question: IIbJjQKWaoGKHGgWPcy, uNoMWaoGKHGqbnjmYQ

Answer: WaoGKHG


Question: yCxlDzWQAqQyU, guvyYDzWQAqtFnUjM

Answer:
DzWQAq