In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
--------
Question: njzfcapS, JDzfcYQh

Answer: zfc


Question: srPyjmTQhdFFMcQ, QQGBdtyjmTQhmfEy

Answer: yjmTQh


Question: utuIgeZuWjCGKAsU, RWIgeZuWjCGkhcEeICD

Answer:
IgeZuWjCG