instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
BVipiZoGXaWdjmDsxWP, yxppsiYkiZoGXaWdjoDRuKW
answer:
iZoGXaWdj


question:
RwqzMTeLMdPx, qaWtYhqzMTeLMdHbWDT
answer:
qzMTeLMd


question:
aCFkrZJTrgsHZBsXa, KairZJTrgsHZBwkbKpcOl
answer:

rZJTrgsHZB