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

Input: Consider Input: mOGzbnDXWnNurkBXtcqZ, NLahGzbnDXWnNYgMTOR

Output: GzbnDXWnN


Input: Consider Input: ChKUlYUTQQBjZMZkgEed, lmQQBjZMZkgdEf

Output: QQBjZMZkg


Input: Consider Input: xcBmPw, IiBmvp


Output: Bm