instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
VeLJEBYpZwxVQlo, EZEBYpZwxVQIxjFj
answer:
EBYpZwxVQ


question:
wLLwjL, arLwXm
answer:
Lw


question:
IJQqdzqdaGEIcdyh, izlVdzqdaGGiPYz
answer:

dzqdaG