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

Input: Consider Input: bOvlVNWf, iivlVzWt

Output: vlV


Input: Consider Input: RMurrwPjlfG, QBKrrwPDkTM

Output: rrwP


Input: Consider Input: yPNuNjWO, yWoaNuNjTW


Output: NuNj