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:
dxy = [[1,0],[-1,0],[0,1],[0,-1]]
n=0
def rec(x,y):
    global n
    if (x<0 or x>=h or y<0 or y>=w) or (visited[x][y] or tile[x][y]!='.'):
        return 0
    visited[x][y] = True
    n += 1
    for (dx,dy) in dxy:
        x2 = x + dx
        y2 = y + dy
        rec(x2,y2)
    return 0

w,h=map(int,input().split())
ans = []
while((w,h)!=(0,0)):
    n=0
    tile = []
    for _ in range(h):
        tile.append(list(input()))
    visited = [[False] * w for _ in range(h)]
    for a in range(h):
        for b in range(w):
            if(tile[a][b]=='@'):
                pos_x = a
                pos_y = b
                tile[a][b]='.'
    rec(pos_x, pos_y)
    ans.append(n)
    w,h=map(int,input().split())
for a in ans:
    print(a)