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:
w,h=map(int,input().split())
while w!=0 or h!=0:
    maps=[]
    flag=False
    ans=0
    for i in range(h):
        k=list(input())
        maps.append(k)
    for i in range(h):
        if flag:
            break
        for j in range(w):
            if maps[i][j]=='@':
                maps[i][j]='#'
                pos_x=i
                pos_y=j
                flag=True
                break
    def check(x,y):
        global maps
        if 0<=x<h and 0<=y<w:
            pass
        else:
            return False
        if maps[x][y]=='#':
            return False
        else:
            return True
    def bfs(x,y):
        global ans
        global maps
        for i in [[0,1],[0,-1],[1,0],[-1,0]]:
            p=i[0]
            q=i[1]
            if check(x+p,y+q):
                ans+=1
                maps[x+p][y+q]='#'
                bfs(x+p,y+q)
    bfs(pos_x,pos_y)
    print(ans+1)
    w,h=map(int,input().split())