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

[Q]: VTwtMVKmrRvL, WLoVtWtMVKmrDCke
[A]: tMVKmr


[Q]: SeXNqRAbKdLuWXgb, npsIWRAbKdLuUWSbvuS
[A]: RAbKdLu


[Q]: xUGQFABNqYOE, BbQwQFABNqpLO
[A]:
QFABNq