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

Ex Input:
PIcbiJj, hedcbiZHF

Ex Output:
cbi


Ex Input:
AkYuNemHGBEDF, uluNemHGAycbWX

Ex Output:
uNemHG


Ex Input:
dsoSsaA, QzFoSsqAl

Ex Output:

oSs