Problem: There is a rectangular room, covered with square tiles. Each tile is colored either red or black. A man is standing on a black tile. From a tile, he can move to one of four adjacent tiles. But he can't move on red tiles, he can move only on black tiles.

Write a program to count the number of black tiles which he can reach by repeating the moves described above.



Input

The input consists of multiple data sets. A data set starts with a line containing two positive integers W and H; W and H are the numbers of tiles in the x- and y- directions, respectively. W and H are not more than 20.

There are H more lines in the data set, each of which includes W characters. Each character represents the color of a tile as follows.

* '.' - a black tile
* '#' - a red tile
* '@' - a man on a black tile(appears exactly once in a data set)


The end of the input is indicated by a line consisting of two zeros.

Output

For each data set, your program should output a line which contains the number of tiles he can reach from the initial tile (including itself).

Examples

Input

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


Output

45
59
6
13


Input

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


Output

45
59
6
13

Solution (in PYTHON3):

Solution:
c = {"#":0,
     "@":1,
     ".":2,
     "*":3}

d = [[0, -1],
     [0, 1],
     [-1, 0],
     [1, 0]]

output = []
while True:
    w, h = input().split()
    w = int(w)
    h = int(h)

    if w == 0:
        break

    tiles = [[0 for i in range(w)] for j in range(h)]
    for i in range(h):
        row = input()
        for j in range(w):
            tiles[i][j] = c[row[j]]
            if tiles[i][j] == 1:
                queue = [(j, i)]

    count = 1
    while queue:
        x, y = queue[0]
        queue.pop(0)

        for ud, rl in d:
            xt = x+ud
            yt = y+rl
            if xt >= 0 and xt <= w-1 and yt >= 0 and yt <= h-1:
                if tiles[yt][xt] == 2:
                    tiles[yt][xt] = 3
                    count += 1
                    queue.append((xt, yt))

    output.append(count)

for num in output:
    print(num)