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

[Q]: wCfNCfxvLRAxBstRTwMSqTn, AhwxfFNCfxvLRAxBrNtf
[A]: NCfxvLRAxB


[Q]: YHLJZrFQ, aSLJZQuo
[A]: LJZ


[Q]: blZuoSIy, CDWZuowF
[A]:
Zuo