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

Input: Consider Input: aiqZheFuLtXAGRCGNBTAX, ssnVdztXAGRCGNBTIqmSJLZcy

Output: tXAGRCGNBT


Input: Consider Input: tWJoKSOAuVhmsomA, emdmnBFJoKSOAuVzSgW

Output: JoKSOAuV


Input: Consider Input: okqFMmxGkyPqFFt, rNFMmxGkHnRsjY


Output: FMmxGk