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

Ex Input:
ATmVEtUuZOgsBUuL, UMUuZOgsBPVT

Ex Output:
UuZOgsB


Ex Input:
OyXwTWbLByC, yODnTWbLWYzc

Ex Output:
TWbL


Ex Input:
OVZxWYzAAxG, rStOxWYzJeoC

Ex Output:

xWYz