| Time Limit | $1$ 秒/Second(s) | Memory Limit | $512$ 兆字节/Megabyte(s) |
| 提交总数 | $773$ | 正确数量 | $505$ | "
| 裁判形式 | 标准裁判/Standard Judge | 我的状态 | 尚未尝试 |
| 难度 | 分类标签 | STL |
Print a Chessboard
Draw a chessboard which has a height of H cm and a width of W cm. For example, the following figure shows a chessboard which has a height of 6 cm and a width of 10 cm.
#.#.#.#.#. .#.#.#.#.# #.#.#.#.#. .#.#.#.#.# #.#.#.#.#. .#.#.#.#.#Note that the top left corner should be drawn by '#'.
The input consists of multiple datasets. Each dataset consists of two integers H and W separated by a single space.
The input ends with two 0 (when both H and W are zero).
For each dataset, print the chessboard made of '#' and '.'.
Print a blank line after each dataset.
3 4
5 6
3 3
2 2
1 1
0 0
#.#.
.#.#
#.#.
#.#.#.
.#.#.#
#.#.#.
.#.#.#
#.#.#.
#.#
.#.
#.#
#.
.#
#