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

Q: fCGEhfHvcRouHzNw, gtjBkhfHvcRouHee

A: hfHvcRouH
****
Q: hGyDyQYdxCCuD, BQiFOyQYdxel

A: yQYdx
****
Q: sjFqYSBnhJfvx, ucFqYSBnhJcCrTUfKp

A:
FqYSBnhJ
****