instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
EOwHDdhJcP, DrIuDdhJYw
answer:
DdhJ


question:
IIbJjQKWaoGKHGgWPcy, uNoMWaoGKHGqbnjmYQ
answer:
WaoGKHG


question:
rAsKsQEYwoYlMUiaOQUCt, LvwoYlMUiaOeOwO
answer:

woYlMUiaO