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:
import queue

while True :
    w,h = map(int,input().split())
    if w==0 and h ==0 :
        break
    maze = [input() for _ in range(h)]
    visited = [[-1]*w for _ in range(h)]
    for i in range(h):
        if "@"  in  maze[i]:
            x_f = i
    for i in range(w):
        if maze[x_f][i] =="@":
            y_f = i
    visited[x_f][y_f] = 1
    q = queue.Queue()
    q.put([x_f,y_f])
    cnt  = 1
    while  not q.empty():
        x,y = q.get()
        for dx,dy in [(1,0),(-1,0),(0,1),(0,-1)]:
            if 0<= x+dx < h and 0<= y+dy < w:
                if visited[x+dx][y+dy] == -1 and maze[x+dx][y+dy]=='.':
                    cnt += 1
                    visited[x+dx][y+dy] = 1
                    q.put([x+dx,y+dy])
    print(cnt)