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

Ex Input:
sJRFPufsaWXNeu, AePufsafc

Ex Output:
Pufsa


Ex Input:
mmDhYqPJC, qThYqxW

Ex Output:
hYq


Ex Input:
xLVJdDpaZBahaPFw, VkdDpaZBahhGYM

Ex Output:

dDpaZBah