In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

Q: eeoJEtGHPDvHck, ezPGHPDvHSf

A: GHPDvH
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Q: txJhzNeBj, qLJhzNesV

A: JhzNe
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Q: pqVxqklbWbigZlv, lFtEklbWbeDMZ

A:
klbWb
****