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.Arrays;
import java.util.Scanner;
//1130 Red and Black

public class Main {
	int height,width,startx,starty;
	Scanner sc = new Scanner(System.in);
	char[][] field;
	boolean[][] visited;
	int count = 0;
	void run(){
		sc = new Scanner(System.in);
		while(true){
			count = 0;
			width = sc.nextInt();
			height = sc.nextInt();
			if(width == 0 && height == 0){
				break;
			}
			sc.nextLine();
			field = new char[height][width];
			visited = new boolean[height][width];
			for(int i = 0; i < visited.length; i++){
				for(int j = 0; j < visited[i].length; j++){
					visited[i][j] = false;
				}
			}

			for(int i = 0; i < height; i++){
				field[i] = sc.nextLine().toCharArray();
				//System.out.println(field[i]);
			}

			for(int i = 0; i < field.length;i++){
				for(int j = 0; j < field[i].length; j++){
					if(field[i][j] == '@'){
						startx = j;
						starty = i;
					}
				}
			}
			count++;
			dfs(starty,startx);
			System.out.println(count);
		}
	}

	public void dfs(int y, int x){
		if(y + 1 < height && visited[y+1][x] == false && field[y+1][x] == '.'){
			visited[y+1][x] = true;
			count++;
			dfs(y+1,x);
		}
		if(y - 1 > -1 && visited[y-1][x] == false && field[y-1][x] == '.'){

			visited[y-1][x] = true;
			count++;
			dfs(y-1,x);
		}
		if(x + 1 < width && visited[y][x+1] == false && field[y][x+1] == '.'){
			visited[y][x+1] = true;
			count++;
			dfs(y,x+1);
		}
		if(x - 1 > -1 && visited[y][x-1] == false && field[y][x-1] == '.'){
			visited[y][x-1] = true;
			count++;
			dfs(y,x-1);
		}
	}

	public static void main(String[] args) {
		// TODO ?????????????????????????????????????????????
		new Main().run();
	}

}