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

Ex Input:
yPODMimvyQPYWHfcM, aZiotMimvyQPZncH

Ex Output:
MimvyQP


Ex Input:
lrBJDRkT, jmBJDrI

Ex Output:
BJD


Ex Input:
sxRiffIifjVCBVJVTTDAqsxxL, GsQdunjVCBVJVTTfmo

Ex Output:

jVCBVJVTT