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

[Q]: mmDhYqPJC, qThYqxW
[A]: hYq


[Q]: hRVyvwHqnN, geHeyvwHqiBiYJ
[A]: yvwHq


[Q]: GgVvPYnlEbJVIA, LRVKhYnlEbAwJ
[A]:
YnlEb