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.Scanner;

//Red and Black
public class Main{

	static int c, h, w;
	static int[][] move = {{1,0},{-1,0},{0,1},{0,-1}};
	static char[][] m;
	
	static void dfs(int i, int j){
		for(int k=0;k<4;k++){
			int ni = i + move[k][0];
			int nj = j + move[k][1];
			if(0<=ni&&ni<h&&0<=nj&&nj<w&&m[ni][nj]!='#'){
				m[ni][nj] = '#';
				c++;
				dfs(ni,nj);
			}
		}
	}
	
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true){
			w = sc.nextInt();
			h = sc.nextInt();
			if((w|h)==0)break;
			m = new char[h][w];
			int si = 0;
			int sj = 0;
			for(int i=0;i<h;i++){
				char[] s = sc.next().toCharArray();
				for(int j=0;j<w;j++){
					m[i][j] = s[j];
					if(s[j]=='@'){
						si = i;
						sj = j;
					}
				}
			}
			c = 1;
			m[si][sj] = '#';
			dfs(si,sj);
			System.out.println(c);
		}
	}
}