instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
qMnjlfIsQRtUlPggCpHqu, gfVndMwYDIsQRtUlPgqBJKCX
answer:
IsQRtUlPg


question:
iJbjApY, ggwbjAws
answer:
bjA


question:
MWsTcCTzLlyisNJ, FGDVTcCTzLlYU
answer:

TcCTzLl