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

[Q]: fdinRdwwlntwqzYGhV, ZefonRdwwlntoWQbh
[A]: nRdwwlnt


[Q]: VLxrvK, gvxrac
[A]: xr


[Q]: TkAOUCIZgP, OdexOUCIpn
[A]:
OUCI