instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
wrVsKN, mOVsWo
answer:
Vs


question:
OjQHcFUCflYUptUPqYKVomn, GXHcFUCflYUpSSTrQ
answer:
HcFUCflYUp


question:
nWTnWqkLqYTBxT, cSTnWqkLqYwXmxRF
answer:

TnWqkLqY