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

Ex Input:
EOacPYivmmUlYenynBqAwx, MoZWMOeXmUlYenynBEendWg

Ex Output:
mUlYenynB


Ex Input:
CxwZWv, mkwZgM

Ex Output:
wZ


Ex Input:
PiWcmACrME, jrMcmACQpoV

Ex Output:

cmAC