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: bmZKWkYPqugcvzbHykblPzQLhK, tPUzKqugcvzbHypzk

Answer: qugcvzbHy


Question: gXwuhXJrEdzGOmLSKdK, TohXJrEdzGavU

Answer: hXJrEdzG


Question: DLHYxroUSCdDq, mTxroUSChhDz

Answer:
xroUSC