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

[Q]: CUlMsvov, iflMsSRp
[A]: lMs


[Q]: MvALRGKkpALcKdhTtnm, neMkRGKkpALcKdcaxnXEPxW
[A]: RGKkpALcKd


[Q]: BadNgr, iTdNSf
[A]:
dN