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

[Q]: yRhCObvPZYoKUoQnyaatR, NHzLJYPZYoKUoQnJnIsZxC
[A]: PZYoKUoQn


[Q]: njzfcapS, JDzfcYQh
[A]: zfc


[Q]: WRqofaidSgzAdB, GucivfaidSLCiHx
[A]:
faidS