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

Ex Input:
nWTnWqkLqYTBxT, cSTnWqkLqYwXmxRF

Ex Output:
TnWqkLqY


Ex Input:
oCtWZYdkvZ, pkktWZYdEHMW

Ex Output:
tWZYd


Ex Input:
oDdulHNcCdgbRGxiBTxM, kDcCdgbRGnsJlvas

Ex Output:

cCdgbRG