instruction:
In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
question:
RpaZAvSnEBgGapIPQgw, wcwYsXvSnEBgGapIwoIWROB
answer:
vSnEBgGapI


question:
nrIHKzJCdAQzUDRBYpg, JDzJCdAQzUMMYrLcfO
answer:
zJCdAQzU


question:
YNNuwqbjj, PKIuwqJau
answer:

uwq