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

[Q]: rcKVmDzwJKeK, uYqmDzwJKxkGi
[A]: mDzwJK


[Q]: mRVieYomZqJXaTDsShCyfPW, ifOAlnptmZqJXaTDsVMqY
[A]: mZqJXaTDs


[Q]: ZDnLRCvLcMFvIb, BfCvLcMot
[A]:
CvLcM