In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.

pqFpUjQGiofBOjfYkRW, pQMnCFlhFpUjQGiofbc
FpUjQGiof

goyZUz, QryZlD
yZ

BAwKkxcDRhlv, VkMKkxcDRkbGMQc

KkxcDR