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

SIIPePlrkftKkzfgdjg, JqNnXHrkftKkzOMUwmc
rkftKkz

VRamNL, mUamIB
am

KoxiPMUXuAV, HNPMUXCqQJ

PMUX