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

Input: Consider Input: CwTYJWQbzEZkvcqKn, hBnhJWQbzEZkKmVM

Output: JWQbzEZk


Input: Consider Input: RpaZAvSnEBgGapIPQgw, wcwYsXvSnEBgGapIwoIWROB

Output: vSnEBgGapI


Input: Consider Input: lMnUPw, KBnUKI


Output: nU