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

Input: Consider Input: hGyDyQYdxCCuD, BQiFOyQYdxel

Output: yQYdx


Input: Consider Input: aiqZheFuLtXAGRCGNBTAX, ssnVdztXAGRCGNBTIqmSJLZcy

Output: tXAGRCGNBT


Input: Consider Input: ewRgqMgGY, iJgqMeIC


Output: gqM