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

Example Input: DhhYhrqVMXSoyvXQwqPKzWARAP, CaMXSoyvXQwqcDDtMsVqD
Example Output: MXSoyvXQwq

Example Input: JKZiYILNeNQbJyznES, PHKILNeNQbJylltYH
Example Output: ILNeNQbJy

Example Input: zPwOdhsTnpNSIFcj, hvPzhsTnpNSInZ
Example Output:
hsTnpNSI