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 location(field, wanted):
    for i, row in enumerate(field):
        for j, cell in enumerate(row):
            if cell == wanted:
                return i, j
def count(field, wanted):
    result = 0
    for row in field:
        for cell in row:
            if cell == wanted:
                result += 1
    return result
def neighborhood(center, w, h):
    i, j = center
    return filter(lambda x: 0 <= x[0] and x[0] < h and 0 <= x[1] and x[1] < w,
                  [                (i - 1, j    ),
                   (i    , j - 1),                 (i    , j + 1),
                                   (i + 1, j    )])
printed_later = []
while True:
    #入力
    w, h = map(int, input().split())
    if(w == 0 and h == 0):
        break
    field = []  # strの配列すなわちcharの配列の配列 '.':黒 '#':赤 '@':スタート (',':到達可能)
    for i in range(h):
        field.append(list(input()))
    #出力　幅優先探索
    queue = [location(field,'@')]
    field[queue[0][0]][queue[0][1]] = ','
    while len(queue) > 0:
        for cell in neighborhood(queue.pop(0), w, h):
            if field[cell[0]][cell[1]] == '.':
                queue.append(cell)
                field[cell[0]][cell[1]] = ','
    printed_later.append(count(field, ','))
for line in printed_later:
    print(line)