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:
def main():
    while 1:
        w, h = map(int, input().split())
        if w == 0: break
        fld = [[] for i in range(h)]
        for i in range(h):
            readline = input()
            for j in range(w):
                item = readline[j]
                fld[i].append(item)
                if item == '@': sy, sx = i, j
        solve(fld, sy, sx)
        count = 0
        for i in range(h):
            for j in range(w):
                if fld[i][j] == 'A': count += 1
        print(count)

def solve(fld, cy, cx):
    vy = [1,-1,0,0]
    vx = [0,0,1,-1]
    fld[cy][cx] = 'A'
    for i in range(4):
        ny = cy + vy[i]
        nx = cx + vx[i]
        if ny < 0 or nx < 0 or ny >= len(fld) or nx >= len(fld[0]):continue
        elif fld[ny][nx] == '.': solve(fld, ny, nx)
main()