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: koddLvYmRXDUuUnW, GnqDYGmmRXDUuUquAnf

Answer: mRXDUuU


Question: uRLpAWCotLmxcSmKyvo, laotLmxcSmKyBwVfJB

Answer: otLmxcSmKy


Question: PoqoATB, quvqoAdxm

Answer:
qoA