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

[Q]: rduIwWNGM, AJqYIwWNaCap
[A]: IwWN


[Q]: BVipiZoGXaWdjmDsxWP, yxppsiYkiZoGXaWdjoDRuKW
[A]: iZoGXaWdj


[Q]: yKtQOhYvrJVH, HQsTQOhYvPP
[A]:
QOhYv