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:
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if __name__ == "__main__":
    while 1:
        w,h = list(map(int,input().strip().split()))
        if w == h == 0:break
        data = []
        data = []
        for _ in range(h):data.append(list(input()))
        visited = []
        position =(0,0)
        for i in range(h):
            if '@'in data[i]:position = (i,data[i].index('@'))
        stack = []
        count = 0
        stack.append(position)
        while len(stack) !=0:
            position = stack.pop()
            count +=1
            if position[0] -1 >= 0 and not (position[0]-1,position[1])in visited and data[position[0] -1][position[1]] == '.':
                visited.append((position[0] -1,position[1]))
                stack.append((position[0] -1,position[1]))
            if position[1] -1 >= 0 and not (position[0],position[1]-1)in visited and data[position[0]][position[1]-1] == '.':
                visited.append((position[0],position[1]-1))
                stack.append((position[0],position[1]-1))
            if position[0] +1 < h and not (position[0]+1,position[1])in visited and data[position[0] +1][position[1]] == '.':
                visited.append((position[0]+1,position[1]))
                stack.append((position[0]+1,position[1]))
            if position[1] + 1 < w and not (position[0],position[1]+1)in visited and data[position[0]][position[1] +1] == '.':
                visited.append((position[0],position[1] +1))
                stack.append((position[0],position[1]+1))

        print(count)