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

[Q]: wNiHcaiUPHnjp, aSTmjcaiUPHFzOu
[A]: caiUPH


[Q]: jinzsW, SMnzaW
[A]: nz


[Q]: wEdtbdJLXctBi, NMaPLdtbdJLXctCJwyi
[A]:
dtbdJLXct