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

[Q]: HSsyZzZLZAAq, MFEZzZLJC
[A]: ZzZL


[Q]: OyrqfQQnzOFUzrkDM, iBkQQnzOFewhjvO
[A]: QQnzOF


[Q]: sqAshmCxL, SoCshmXA
[A]:
shm