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: aBlALASwuwTZmy, MdwASwuwIW

Answer: ASwuw


Question: vMYfFo, EHYfnP

Answer: Yf


Question: qEddfgFfv, kROdfgFxUsr

Answer:
dfgF