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

Q: NUuLSmDjCKcJPc, lGGSLIDjCKcJBo

A: DjCKcJ
****
Q: jeQzwP, kSQzxq

A: Qz
****
Q: rHOOZVdDUnomXmiWJ, BxHdDUnomLpevV

A:
dDUnom
****