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

Ex Input:
esIMEOgV, tNIMEybb

Ex Output:
IME


Ex Input:
IzwlZDJSEFPxfIud, xwWSYwlZDJSEFPbvSXTlS

Ex Output:
wlZDJSEFP


Ex Input:
HYOVwhHxsZt, tDwhHxsoNl

Ex Output:

whHxs