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: VutZiVkDQcVpQO, BDQVDyBdiVkDQcVpuvNN

Answer: iVkDQcVp


Question: goyZUz, QryZlD

Answer: yZ


Question: eaYXBenklGCefRYKxsTQUBDTr, xckbVIQPhklGCefRYKxVkpG

Answer:
klGCefRYKx