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

Ex Input:
pqFpUjQGiofBOjfYkRW, pQMnCFlhFpUjQGiofbc

Ex Output:
FpUjQGiof


Ex Input:
JjEQVKijeyEQ, dwSVKijeywCTvb

Ex Output:
VKijey


Ex Input:
TsSCpWEB, YdRSCpSfB

Ex Output:

SCp