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

[Q]: HhBhJMpxpty, MxTJMpxnQEf
[A]: JMpx


[Q]: XmiLktrUjJDOCJ, UIKrUjJDOQsR
[A]: rUjJDO


[Q]: BbksnsLCDbwhUVoXpt, mFNMTLCDbwhYduL
[A]:
LCDbwh