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

[Q]: XEvxzelZaWRO, zXIelZaWBUn
[A]: elZaW


[Q]: OFbCjZDoRRlLsMU, DcCjZDoRRtld
[A]: CjZDoRR


[Q]: qtgBFSEh, pIBFSZDu
[A]:
BFS