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
{
    int dx[]={-1,0,1,0};
    int dy[]={0,1,0,-1};
    char[][] map;
    void run()
    {
	Scanner sc=new Scanner(System.in);
	while(true){
	    int W=sc.nextInt();
	    int H=sc.nextInt();sc.nextLine();
	    if(W==0&&H==0)break;
	    
	    int startX=0,startY=0;
	    map=new char[H+2][W+2];
	    for(int i=0;i<H+2;i++){
		Arrays.fill(map[i],'#');
	    }
	    for(int i=1;i<H+1;i++){
		char[] s=sc.next().toCharArray();
		for(int j=0;j<W;j++){	
		    if(s[j]=='@'){
			startY=i;
			startX=j+1;
		    }
		    map[i][j+1]=s[j];	
		}
	    }
	    System.out.println(DFS(startY,startX));
	}
    }
    int DFS(int y,int x)
    {
	if(map[y][x]=='#')return 0;
	map[y][x]='#';
	int sum=1;
	for(int i=0;i<4;i++){
	    sum+=DFS(y+dy[i],x+dx[i]);
	}
	return sum;
    }
    
    public static void main(String[] args)
    {
	new Main().run();
    }
}