instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
XSnVeAjWLFWTgwmf, WsByLAjWLFWnQfl
answer:
AjWLFW


question:
CdRbREFMEDTXnEzgn, zHLEMMEDTXnEPH
answer:
MEDTXnE


question:
AVEnAzCxsdUYbJxPR, uqEKzCxsdUhJKnM
answer:

zCxsdU