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

[Q]: mJoHBJehHtkFS, ZMrDxHBJehHtxS
[A]: HBJehHt


[Q]: RwduMBkDazrwZP, UPzcwtWMBkDazrAw
[A]: MBkDazr


[Q]: iWRvMRPzIIc, skvMRPYh
[A]:
vMRP