instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
kOrQWjLKnwN, xFsWjLKgr
answer:
WjLK


question:
OUNqomxFcLXhWdfB, gdqomxFcLHQPCu
answer:
qomxFcL


question:
soFTerofIgUmuIR, rVBrofIgUmuDB
answer:

rofIgUmu