AT_abc395_b [ABC395B] Make Target

> **Overview**: Create an $ N \times N $ pattern as follows. ``` > > ########### > #.........# > #.#######.# > #.#.....#.# > #.#.###.#.# > #.#.#.#.#.# > #.#.###.#.# > #.#.....#.# > #.#######.# > #.........# > ########### > ``` You are given a positive integer $ N $ . Consider an $ N \times N $ grid. Let $ (i,j) $ denote the cell at the $ i $ -th row from the top and the $ j $ -th column from the left. Initially, no cell is colored. Then, for $ i = 1,2,\dots,N $ in order, perform the following operation: - Let $ j = N + 1 - i $ . - If $ i \leq j $ , fill the rectangular region whose top-left cell is $ (i,i) $ and bottom-right cell is $ (j,j) $ with black if $ i $ is odd, or white if $ i $ is even. If some cells are already colored, overwrite their colors. - If $ i > j $ , do nothing. After all these operations, it can be proved that there are no uncolored cells. Determine the final color of each cell.

The input is given from Standard Input in the following format: > $ N $

Print $ N $ lines. The $ i $ -th line should contain a length- $ N $ string $ S_i $ representing the colors of the $ i $ -th row of the grid after all operations, as follows: - If cell $ (i,j) $ is finally colored black, the $ j $ -th character of $ S_i $ should be `#`. - If cell $ (i,j) $ is finally colored white, the $ j $ -th character of $ S_i $ should be `.`.

### Sample Explanation 1 This matches the pattern shown in the **Overview**. ### Sample Explanation 2 Colors are applied as follows, where `?` denotes a cell not yet colored: ``` i=1 i=2 i=3 i=4 i=5 ????? ##### ##### ##### ##### ##### ????? ##### #...# #...# #...# #...# ????? -> ##### -> #...# -> #.#.# -> #.#.# -> #.#.# ????? ##### #...# #...# #...# #...# ????? ##### ##### ##### ##### ##### ``` ### Constraints - $ 1 \leq N \leq 50 $ - All input values are integers.