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;
public class Main{
	static char map[][]=new char[20][20];
	static int ans; 
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true){
			int w=sc.nextInt();
			int h=sc.nextInt();
			int x=0,y=0;
			ans=0;
			if(w==0&&h==0)break;
			for(int i=0;i<h;i++){
				String str=sc.next();
				for(int j=0;j<w;j++){
					map[i][j]=str.charAt(j);
					if(map[i][j]=='@'){
						x=j;y=i;
					}
				}
			}
			dfs(x, y, w, h);
			System.out.println(ans);
		}
	}
	
	public static void dfs(int x,int y,int w, int h){
		int x_m[]={1,0,-1,0};
		int y_m[]={0,1,0,-1};
		ans++;
		for(int i=0;i<4;i++){
			int nx=x+x_m[i];
			int ny=y+y_m[i];
			map[y][x]='#';
			if(0<=nx&&0<=ny&&nx<w&&ny<h&&map[ny][nx]=='.'){
				dfs(nx, ny, w, h);
			}
		}
		
	}
}