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

[Q]: CdRbREFMEDTXnEzgn, zHLEMMEDTXnEPH
[A]: MEDTXnE


[Q]: oWwqraAz, uxTqraonu
[A]: qra


[Q]: JXnHYuZvAYK, zhUYuZvASGhd
[A]:
YuZvA