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.*;

public class Main{
	public static char[][] map;
	public static int[] dx = {0,0,1,-1};
	public static int[] dy = {1,-1,0,0};

	public static int dfs(int x, int y){
		int ans=1;
		map[y][x] = '#';
		for(int i=0;i<4;i++){
			int nx = x + dx[i];
			int ny = y + dy[i];
			if(0<=nx && nx<map[0].length && 0<=ny && ny<map.length && map[ny][nx] == '.'){
				ans += dfs(nx,ny);
			}
		}
		return ans;
	}

	public static void main(String[] args){
		Scanner sc= new Scanner(System.in);

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

			map = new char[h][w];
			int x=0, y=0;
			for(int i=0;i<h;i++){
				map[i] = sc.next().toCharArray();
				for(int j=0;j<w;j++){
					if(map[i][j]=='@'){x=j; y=i; map[i][j]='.';}
				}
			}
			System.out.println(dfs(x,y));
		}
	}
}