一个矩形房间由正方形瓷砖铺成。. 表示黑砖，# 表示红砖，@ 表示站在黑砖上的起点。人只能在黑砖之间上下左右移动。

对每组房间数据，求从 @ 出发能够到达的黑砖总数，起点所在砖也计入。

输入格式

输入包含多组数据。

每组数据第一行两个整数 $W,H$，分别表示列数和行数；随后 $H$ 行，每行包含 $W$ 个字符。

输入以 0 0 结束，这一行不需要处理。

输出格式

每组数据输出一行，表示能够到达的黑砖数量。

6 9
....#.
.....#
......
......
......
......
......
#@...#
.#..#.
11 9
.#.........
.#.#######.
.#.#.....#.
.#.#.###.#.
.#.#..@#.#.
.#.#####.#.
.#.......#.
.#########.
...........
11 6
..#..#..#..
..#..#..#..
..#..#..###
..#..#..#@.
..#..#..#..
..#..#..#..
7 7
..#.#..
..#.#..
###.###
...@...
###.###
..#.#..
..#.#..
0 0

45
59
6
13

11 11
.....#.###.
.#.....#...
#....####.#
#.##....@..
..#.....##.
...#.....#.
.#...#..#..
#.#.....#..
..#........
.#.#..##...
#.#....##..
0 0

80

15 17
###.....##..#..
...#.##..#.##..
..............#
.....#........#
..##.......####
.#......#......
.#.#...#.#....#
#.......#..####
..#.#.#..##..##
...#..##.......
##....#...#....
##.####.....##.
..#..#...#..#..
#........#.#@##
..##.###.#..#..
.........#..##.
..##..#.#.##...
18 19
...#....##........
.##.#..#..#.......
..#.#.#........#..
.....#.#.######.#.
....#...##.##.#...
#.#.....##.##...##
....#.....#@..#.#.
.#...........#..#.
.......#.###...#..
.#..##.##..#..##..
...#.#...#....#.#.
#.#..#...##....##.
.#..##.##.......#.
..#.#.#.#.#..#....
......#.#.#..#...#
...#..#...#.#.#...
...##.....#.#..#..
#..............#.#
.##...#.#........#
0 0

1
229

数据范围

$1\le W,H\le20$。每组数据恰有一个 @。