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

[Q]: vFuggVITQuctFG, hdCIWWuuggVITQwr
[A]: uggVITQ


[Q]: JIOKyo, oPOKsX
[A]: OK


[Q]: kmsgTX, jNsgyG
[A]:
sg