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

Input: Consider Input: KKebLWQCQzVIojj, nxQCQzVIopD

Output: QCQzVIo


Input: Consider Input: iaXeqfIrYKxPJRXxfSm, rIYKxPJRXxfsjVsqe

Output: YKxPJRXxf


Input: Consider Input: cAfqpDnrFmAOcFrQRtfUyo, huJnrFmAOcFCLRSQbha


Output: nrFmAOcF