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

iUtNuU, iKtNWk
tN

SUgXyznbUQRpiLUTlRb, jlnwLTnbUQRpioUFyJ
nbUQRpi

bfkfZELQ, CtfZESkH

fZE