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

[Q]: wbFDXJQDQxQJzudOUlR, QEbsIDXJQDQxQsSYIutwU
[A]: DXJQDQxQ


[Q]: iYSNsY, HSSNhP
[A]: SN


[Q]: TEXePoLvYpfsEkl, DSoLvYpfOzGzR
[A]:
oLvYpf