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

Ex Input:
EOwHDdhJcP, DrIuDdhJYw

Ex Output:
DdhJ


Ex Input:
gfDDsblwUryUw, UWaRisblwUTqTM

Ex Output:
sblwU


Ex Input:
XxTIDbmbRrXKPRsALTWzUvyg, eJANFntXKPRsALTWzcqo

Ex Output:

XKPRsALTWz