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

IzwlZDJSEFPxfIud, xwWSYwlZDJSEFPbvSXTlS
wlZDJSEFP

QzJdafaGRLWEguLkOaw, brmPLBoaGRLWEguEaF
aGRLWEgu

meUUZGRNyuLNuXjji, lehZGRNyuLNuXOUkw

ZGRNyuLNuX