instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
gHFwDorPbNPORVgdLW, AfqDQvCGFwDorPbNPVPVmbQ
answer:
FwDorPbNP


question:
iYuUgULgqcAgd, kRNUgULgqFv
answer:
UgULgq


question:
axZNlYvZaNO, VAlYvZGqR
answer:

lYvZ