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

Input: Consider Input: IGHhMfqLeBpnullsPInfBH, LTDBpnullsPIBynwCrCQ

Output: BpnullsPI


Input: Consider Input: dReySjyqecU, loSjyqiRl

Output: Sjyq


Input: Consider Input: WbwbDeqXdfsDBiGynjlxuF, UOqXdfsDBiiTnjE


Output: qXdfsDBi