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: KJswoapnXz, EQswoaFyH

Answer: swoa


Question: yiKkIxbKvNk, znaIxbKggg

Answer: IxbK


Question: vcdIgLmN, UidIgLxNJ

Answer:
dIgL