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: KfjqnJLciTXqkJK, yqfRcfqnJLcisSB

Answer: qnJLci


Question: rcKVmDzwJKeK, uYqmDzwJKxkGi

Answer: mDzwJK


Question: hhmgACvogbHDG, rAXmgACvogHA

Answer:
mgACvog