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

DwLGzwYOWjtzIunE, TTViSbkwYOWjtzNqUOOz
wYOWjtz

FgQsxN, UMQsIa
Qs

QIPZgIKZxFmWUZvuRQ, oJjTSEKZxFmWmspVK

KZxFmW