instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
koddLvYmRXDUuUnW, GnqDYGmmRXDUuUquAnf
answer:
mRXDUuU


question:
GFhJafTV, waHhJaji
answer:
hJa


question:
JzGBArAFORbVBa, vShArAFOUTkD
answer:

ArAFO