instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
yjoJzBGdwfOhsceoOpoap, uSLMdBGdwfOhsIQHBijd
answer:
BGdwfOhs


question:
BTvLVMYp, mjOvLVMqYo
answer:
vLVM


question:
cXHonpTKDMdPUttoPBpRRZhjy, kbjnKDMdPUttoPsBr
answer:

KDMdPUttoP