instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
nhGinCtvLartcMPhJwGRbpZNrq, iQJlFKayEartcMPhJwDRROB
answer:
artcMPhJw


question:
DhhYhrqVMXSoyvXQwqPKzWARAP, CaMXSoyvXQwqcDDtMsVqD
answer:
MXSoyvXQwq


question:
FlLtMuatqIKRAjQ, AGvkLtMuatqoDaecgs
answer:

LtMuatq