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 Check(A, i, j, W, H) :
    if j-1 >= 0 :
        if A[i][j-1] == "." :
            A[i][j-1] = "+"
            Check(A, i, j-1, W, H)
    if i+1 < H :
        if A[i+1][j] == "." :
            A[i+1][j]= "+"
            Check(A, i+1, j, W, H)
    if j+1 < W :
        if A[i][j+1] == "." :
            A[i][j+1] = "+"
            Check(A, i, j+1, W, H)
    if i-1 >= 0 :
        if A[i-1][j] == "." :
            A[i-1][j] = "+"
            Check(A, i-1, j, W, H)
    return(A)

while True :
    W, H = map(int, input().split())
    if W == 0 and H == 0 :
        break
    
    Tile = [list(input()) for i in range(H)]
    for i in range(H) :
        for j in range(W) :
            if Tile[i][j] == "@" :
                my_i = i
                my_j = j
    Tile[my_i][my_j] = "+"
    Tile_new = Check(Tile, my_i, my_j, W, H)
    count = 0
    for i in range(H) :
        for j in range(W) :
            if Tile_new[i][j] == "+" :
                count += 1
    print(count)