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

[Q]: wLLwjL, arLwXm
[A]: Lw


[Q]: CuizrSvJTRWZK, udyrSvJTRZzkS
[A]: rSvJTR


[Q]: XcjQfPwXr, goZNJjQfPwunFA
[A]:
jQfPw