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 {
	
	static char board[][] = new char[30][30];
	static int dx[] = {1,-1, 0, 0};
	static int dy[] = {0, 0, 1, -1};
	
	public static void main(String args[]){
		Scanner in = new Scanner(System.in);
		while(true){
			int w = in.nextInt(), h = in.nextInt();
			if(w==0 && h==0) return;
			int sx=0, sy=0;
			for(int i=0; i<30; i++)for(int j=0; j<30; j++) board[i][j] = '#';
			for(int i=1; i<=h; i++){
				String line = in.next();
				for(int j=1; j<=w; j++){
					board[i][j] = line.charAt(j-1);
					if(board[i][j] == '@'){
						sx = i;
						sy = j;
						board[i][j] = '.';
					}
				}
			}
			dfs(sx,sy);
			int cnt=0;
			for(int i=1; i<=h; i++)
				for(int j=1; j<=w; j++)
					if(board[i][j] == '@')
						cnt++;
			System.out.println(cnt);
		}
	}
	
	private static void dfs(int i, int j){
		if(board[i][j] != '.') return ;
		board[i][j] = '@';
		for(int k=0; k<4; k++){
			dfs(i+dx[k], j+dy[k]);
		}
		return ;
	}
}