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: wbdHVigIkjNkuAmbr, iSgIkjNkQYyn

Answer: gIkjNk


Question: Owbiay, exbime

Answer: bi


Question: YqnGQpre, RfhnGQucZ

Answer:
nGQ