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:
vx = [1, -1, 0, 0]
vy = [0, 0, 1, -1]


def isBound(n, m, x, y):
    return x < 0 or y < 0 or x >= n or y >= m


def dfs(x, y):
    global field
    global cnt
    global v

    if isBound(W, H, x, y):
        return
    if field[y][x] == '#':
        return
    if v[y][x]:
        return
    else:
        v[y][x] = True
        cnt += 1

    for i in range(4):
        nx = x + vx[i]
        ny = y + vy[i]
        dfs(nx, ny)

while True:
    W, H = map(int, raw_input().split())

    if W == 0:
        break

    field = []
    for h in range(H):
        field.append(raw_input())

    v = [[False for i in range(W)] for j in range(H)]

    cnt = 0
    for x in range(W):
        for y in range(H):
            if field[y][x] == '@':
                dfs(x, y)
    print cnt