#递归

AtCoder Beginner Contest 357-C

ProblemFor a non-negative integer , we define a level- carpet as follows: A level- carpet is a grid consisting of a single black cell. For , a level- carpet is a grid. When this grid is divided into nine blocks: The central block consists entirely of white cells. The other eight blocks are level- carpets. You are given a non-negative integer . Print a level- carpet according to the specified fo...