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: TvNVpHLPYjBCeUpyxlzFZ, tgKdPKVYjBCeUpyPK

Answer: YjBCeUpy


Question: hRVyvwHqnN, geHeyvwHqiBiYJ

Answer: yvwHq


Question: gyxRlqlCyWqRZToxKNYJXJ, oSfMdpEaMWqRZToxKNupctHFT

Answer:
WqRZToxKN