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

Q: JXnHYuZvAYK, zhUYuZvASGhd

A: YuZvA
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Q: mQvintdwLUpClREgxv, rYnoXBtdwLUpClRwxsqX

A: tdwLUpClR
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Q: boVaJiNvQtitR, FQEaJiNvQBem

A:
aJiNvQ
****