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 PYTHON):

Solution:
dx = [-1,0,1,0]; dy = [0,-1,0,1];
while 1:
    w,h = map(int, raw_input().split())
    if w==h==0: break;
    m = []; s = []; sx = sy = 0;
    m.append('#'*(w+2))
    for i in range(h):
        m.append("#"+raw_input()+"#")
    m.append('#'*(w+2))
    f = [[0 for i in range(w+2)] for j in range(h+2)]
    for i in range(1,h+1):
        for j in range(1,w+1):
            if m[i][j]=='@':
                sx = j; sy = i;
    s.append([sx,sy]);
    f[sy][sx] = 1; ans = 1;
    while len(s)>0:
        x,y = s.pop(0)
        for k in range(4):
            if m[y+dy[k]][x+dx[k]]!='#' and f[y+dy[k]][x+dx[k]]==0:
                s.append([x+dx[k],y+dy[k]])
                f[y+dy[k]][x+dx[k]] = 1; ans += 1;
    print ans