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

Q: vSFxjd, AHFxpi

A: Fx
****
Q: eMDNXl, ZZDNAa

A: DN
****
Q: WccDCNccuMBhXJiGuZ, NJJPRIuMBhXJiGBjA

A:
uMBhXJiG
****