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: QzJdafaGRLWEguLkOaw, brmPLBoaGRLWEguEaF

Answer: aGRLWEgu


Question: oGaGjsaKsUpLQAg, iDGjsaKsUoYGuta

Answer: GjsaKsU


Question: jweiKqFZaoH, lGViKqFZFBqBw

Answer:
iKqFZ