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

[Q]: ugDpSMRvHM, DDwSMRvxw
[A]: SMRv


[Q]: hVQJkZyKfPoOQEukfAbXDpB, qpojyxWkZyKfPoOQEZkUI
[A]: kZyKfPoOQE


[Q]: TNcqHKhiZ, oQyFqHKhFwXw
[A]:
qHKh