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

Q: hVQJkZyKfPoOQEukfAbXDpB, qpojyxWkZyKfPoOQEZkUI

A: kZyKfPoOQE
****
Q: yxJxNRLEnKGHziJtfb, KfReWhEnKGHzitzfPWzK

A: EnKGHzi
****
Q: ErXCJr, LlXCan

A:
XC
****