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

[Q]: aeQjEeiWGONmzGimhGiw, RIEeiWGONmOZuVYr
[A]: EeiWGONm


[Q]: CUxfOt, dyxfNp
[A]: xf


[Q]: EjNAtwKhXW, zEAtwKhHJBuN
[A]:
AtwKh