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

[Q]: cjDuPZOHjystHnF, okWVdUDuPZOHjSCaEecP
[A]: DuPZOHj


[Q]: OezHeoe, ouUzHemU
[A]: zHe


[Q]: zlbFtYcjvtmTRbdse, RSMbFtYcjvtLlXZ
[A]:
bFtYcjvt