instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
RGImMTISYdkjzMO, pmyfpImMTISYdatLBBFr
answer:
ImMTISYd


question:
NTINFnRckGsfLqhSoA, UUONcKKFnRckGsfLqVak
answer:
FnRckGsfLq


question:
lNnkyCpWMhWV, whUnkyCptZWI
answer:

nkyCp