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

bOvlVNWf, iivlVzWt
vlV

iupYjFXrrMqWzJSLUSwmEukHc, hqajjWrrMqWzJSLnF
rrMqWzJSL

HbyepfLvpmTMqcebbGOBr, KnmPwzqgfLvpmTMqWPyp

fLvpmTMq