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

Input: Consider Input: sCMyALRSDknURKqZDlqFf, oEIfHyALRSDknUrnMebev

Output: yALRSDknU


Input: Consider Input: OjQHcFUCflYUptUPqYKVomn, GXHcFUCflYUpSSTrQ

Output: HcFUCflYUp


Input: Consider Input: sYRvOkRKDqGEWFoTCOAlCi, ADMKhikRKDqGEWFoapRjE


Output: kRKDqGEWFo