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

IIbJjQKWaoGKHGgWPcy, uNoMWaoGKHGqbnjmYQ
WaoGKHG

egYXVtCPvWxP, VMOolyVtCPvWjIx
VtCPvW

xwBEokhFSjoitfNFF, TkTFSjoitfNym

FSjoitfN