instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
MSxTzCpiJAplpzSvLlNJS, oScCpiJAplpNVrqkn
answer:
CpiJAplp


question:
IJQqdzqdaGEIcdyh, izlVdzqdaGGiPYz
answer:
dzqdaG


question:
rNfCfcapPfnvU, gKMPCfcapPfApcNkWv
answer:

CfcapPf