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

Input: Consider Input: PnRypl, HvRydi

Output: Ry


Input: Consider Input: sdGIVJPsWWszKPCGk, ghRJPsWWszKcJUg

Output: JPsWWszK


Input: Consider Input: llmdFXxHkKUvJOEbjmJGd, HrIoZsHkKUvJOxiDj


Output: HkKUvJO