TASK DEFINITION: In this task, you are given two strings A, B. Find the longest common substring in the strings A and B.
PROBLEM: NmtypJ, tQtyZD

SOLUTION: ty

PROBLEM: wnIFoRQvMMKMAqpCQYncuWUTJs, bPMUKKxYRxQvMMKMAqpCmzAPPMD

SOLUTION: QvMMKMAqpC

PROBLEM: ZbzwibzSdJiaQkffYnvdnx, OANuxLYXibzSdJiaQAvNS

SOLUTION:
ibzSdJiaQ