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

Input: Consider Input: wbFDXJQDQxQJzudOUlR, QEbsIDXJQDQxQsSYIutwU

Output: DXJQDQxQ


Input: Consider Input: WTnsmP, INnsIM

Output: ns


Input: Consider Input: TFgPSwdmRU, lShpgPSwRoMO


Output: gPSw