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: pJqqIW, Ivqqxw

Answer: qq


Question: yywhNdZQkLSzbOvhluicHA, lfZQkLSzbOvhVC

Answer: ZQkLSzbOvh


Question: IpcARrEJgrlN, UpFlRrEJVuB

Answer:
RrEJ