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 '#'.

Constraints

• 1 ≤ H ≤ 300
• 1 ≤ W ≤ 300

Input

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).

Output

For each dataset, print the chessboard made of '#' and '.'.

Print a blank line after each dataset.

Example

Input

3 4 5 6 3 3 2 2 1 1 0 0

Output

#.#. .#.# #.#.

#.#.#. .#.#.# #.#.#. .#.#.# #.#.#.

#.# .#. #.#

#. .#

inputFormat

Input

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).

outputFormat

Output

For each dataset, print the chessboard made of '#' and '.'.

Print a blank line after each dataset.

Example

Input

3 4 5 6 3 3 2 2 1 1 0 0

Output

#.#. .#.# #.#.

#.#.#. .#.#.# #.#.#. .#.#.# #.#.#.

#.# .#. #.#

#. .#

样例

3 4
5 6
3 3
2 2
1 1
0 0

#.#.
.#.#
#.#.
#.#.#.
.#.#.#
#.#.#.
.#.#.#
#.#.#.
#.#
.#.
#.#
#.
.#
#

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