instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
eedZoMwKgDhdsgs, kMMwKgDLm
answer:
MwKgD


question:
rRmkmETbjzCzZZxihrVdefxfcenJ, ogQtzAgWjKCzZZxihrVdRswMCmngp
answer:
CzZZxihrVd


question:
FRokKTfZlXAY, bOhokKTfZlRta
answer:

okKTfZl