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

Ex Input:
dlzequypR, Puequqv

Ex Output:
equ


Ex Input:
DFRoMPNDAzNgtLsEPseOzC, qykyPjDAzNgtLsEPYTsNrJaNK

Ex Output:
DAzNgtLsEP


Ex Input:
WIcfzlvE, nNlcfzeFI

Ex Output:

cfz