instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
ZRjPgqbLL, uIsmPgqbBB
answer:
Pgqb


question:
MSxTzCpiJAplpzSvLlNJS, oScCpiJAplpNVrqkn
answer:
CpiJAplp


question:
LNwJXMigwfcdnzeAgI, hQKfjwJXMigwfcNJL
answer:

wJXMigwfc


