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.LinkedList;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int W = sc.nextInt();
			int H = sc.nextInt();
			if (W == 0 && H == 0) {
				break;
			}
			
			char[][] tile = new char[W][H];
			boolean[][] visited = new boolean[W][H];
			
			int sx = 0;
			int sy = 0;
			for(int i = 0; i < H; i++) {
				String line = sc.next();
				for(int j = 0; j < W; j++) {
					tile[j][i] = line.charAt(j);
					
					if(tile[j][i] == '@') {
						sx = j;
						sy = i;
					}
				}
			}
			LinkedList<XY> queue = new LinkedList<XY>();
			
			// init 
			int count = 0;
			queue.offer(new XY(sx, sy));
			
			while(queue.size() > 0) {
				bfs(W, H, queue, tile, visited);
				count++;
			}
			System.out.println(count);
		}
	}
	
	public static void bfs(int W, int H, LinkedList<XY> queue, char[][] tile, boolean[][] visited) {
		XY current = queue.poll();
		int cx = current.x;
		int cy = current.y;
		
		int[] dx = new int[]{0, 1, 0, -1};
		int[] dy = new int[]{1, 0, -1, 0};
		for(int i = 0; i < dx.length; i++) {
			int x = cx + dx[i];
			int y = cy + dy[i];
			if (x >= 0 && x < W && y >= 0 && y < H && !visited[x][y] && tile[x][y] == '.') {
				queue.offer(new XY(x, y));
				visited[x][y] = true;
			}
		}
	}
}

class XY {
	int x;
	int y;
	XY(int x, int y) { 
		this.x = x;
		this.y = y;
	}
}