instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
JzbEpAquDJFKcNvEWZxVqRV, PFiJlpAquDJFKcNcqOpMeAv
answer:
pAquDJFKcN


question:
XWKEpwGRkfCFZGOyZQOoypx, lhQkmVqeRkfCFZGOyugPLqs
answer:
RkfCFZGOy


question:
bXFbDZQxUyglCfuKZA, EcQxUyglCfNFwjX
answer:

QxUyglCf