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

[Q]: JXnHYuZvAYK, zhUYuZvASGhd
[A]: YuZvA


[Q]: srPyjmTQhdFFMcQ, QQGBdtyjmTQhmfEy
[A]: yjmTQh


[Q]: JdGSUrawnkeiXzQgRGRABsm, qsQkeiXzQgRGNoRJY
[A]:
keiXzQgRG