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

[Q]: OezHeoe, ouUzHemU
[A]: zHe


[Q]: tGBRASi, QABRAtL
[A]: BRA


[Q]: NZwWiNXYBYWOGvJqkh, HfeEuXzJHXYBYWOGvJWTzkKEiTK
[A]:
XYBYWOGvJ