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 JAVA):

Solution:
import java.util.*;

class Main{

    int w, h;
    char[][] map;

    void solve(){
        Scanner sc = new Scanner(System.in);

        while(true){
            w = sc.nextInt(); h = sc.nextInt();
            if(w==0 && h==0) break;

            map = new char[h][w];
            int sx = 0, sy = 0;
            for(int i=0; i<h; i++){
                map[i] = sc.next().toCharArray();
                for(int j=0; j<w; j++){
                    if(map[i][j]=='@'){ sx = j; sy = i;}
                }
            }

            System.out.println(bfs(sx, sy));
        }
    }

    int[] dx = {1, -1, 0, 0};
    int[] dy = {0, 0, 1, -1};

    int bfs(int sx, int sy){
        LinkedList<int[]> q = new LinkedList<int[]>();
        q.add(new int[]{sx, sy});
        boolean[][] v = new boolean[h][w];
        int cnt = 0;

        while(q.size()>0){
            int[] qq = q.poll();
            int x = qq[0], y = qq[1];

            if(v[y][x]) continue;
            v[y][x] = true;
            cnt++;

            for(int i=0; i<4; i++){
                int nx = x + dx[i], ny = y + dy[i];
                if(nx<0 || nx>=w || ny<0 || ny>=h || map[ny][nx]=='#') continue;
                q.add(new int[]{nx, ny});
            }
        }
        return cnt;
    }

    public static void main(String[] args){
        new Main().solve();
    }
}