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

[Q]: GoodBOwvrki, kRCsdBOwvrakgiH
[A]: dBOwvr


[Q]: zqRbqwgmqGIAGTeeoGFOSr, RFnLqwgmqGIAGLcEvAWxY
[A]: qwgmqGIAG


[Q]: frvbYaev, fTbYavq
[A]:
bYa