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

[Q]: iaXeqfIrYKxPJRXxfSm, rIYKxPJRXxfsjVsqe
[A]: YKxPJRXxf


[Q]: DwkTGsIXLfmjMV, VqRlMxtsSBkTGsIXLfmjbvI
[A]: kTGsIXLfmj


[Q]: TWVTGNBh, nEVTGWq
[A]:
VTG