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

[Q]: HaLZdTX, tLLZdEXN
[A]: LZd


[Q]: rcKVmDzwJKeK, uYqmDzwJKxkGi
[A]: mDzwJK


[Q]: UYtVNXmJXpLjyi, jWzrFWtVNXmJXvBhbD
[A]:
tVNXmJX