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

Input: Consider Input: FiKGCRXutEOzMqP, xdxRXutEsl

Output: RXutE


Input: Consider Input: JIOKyo, oPOKsX

Output: OK


Input: Consider Input: EnqDcqgOryFZfKXL, XnLSYTUGLqDcqgOryFZiHH


Output: qDcqgOryFZ