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:
#演習2-22
def solve(w,h,tile):
    # スタート地点探索
    ok = False
    for y in range(h):
        for x in range(w):
            if tile[y][x] == "@":
                s_x = x
                s_y = y
                ok = True
                break
        if ok:
            break
    # 幅優先探索
    count = 0
    check = [[s_x, s_y]]
    check_map = [[False for j in range(w)] for i in range(h)]
    while len(check) > 0:
        x, y = check.pop(0)
        if x in range(w) and y in range(h):
            if check_map[y][x] == False:
                if tile[y][x] == "." or tile[y][x] == "@":
                    check_map[y][x] = True
                    count += 1
                    check.append([x, y-1])
                    check.append([x, y+1])
                    check.append([x+1, y])
                    check.append([x-1, y])
    return count

while True:
    try:
        w, h = map(int, input().split())
        if w == 0:
            break
        tile = [""] * h
        for i in range(h):
            tile[i] = input()

        print(solve(w,h,tile))
    except:
        break