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

Ex Input:
DQVkAbWTTPhoBx, TeWTTPhonxcIKL

Ex Output:
WTTPho


Ex Input:
rRmkmETbjzCzZZxihrVdefxfcenJ, ogQtzAgWjKCzZZxihrVdRswMCmngp

Ex Output:
CzZZxihrVd


Ex Input:
UbrWBFdNJAjAKeD, lrBFdNJAjaXs

Ex Output:

BFdNJAj