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

aZcGMvzBhazkCIFqpVe, AOljBvzBhazkWXeTuA
vzBhazk

BICndZkjoSidWivWATvtqsS, FzVWjoSidWivFaQhkRT
joSidWiv

pgxhJVAFQvfgVIwLy, ZhCjAFQvfgBlD

AFQvfg