instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
jAinxmaQUrmu, jqeEnxmaQUrWlrEqW
answer:
nxmaQUr


question:
RpaZAvSnEBgGapIPQgw, wcwYsXvSnEBgGapIwoIWROB
answer:
vSnEBgGapI


question:
RZgbcJ, jAgbFs
answer:

gb