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: HLtkkRnWkgIdqbQH, dWeFUtkkRnWkgIdZhlQh

Answer: tkkRnWkgId


Question: oZZUNCUHtIiauDxQ, OdindZUNCUHtIiLQmWJJf

Answer: ZUNCUHtIi


Question: pfmNrYuDkIXtsuEjbv, btIxYuDkIXtnfusqh

Answer:
YuDkIXt