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.*;
public class Main {
	static int cnt;
	static char[][] map = new char[21][21];
	static int w,h;
	static int dfs(int y, int x, char[][] v){
		  int my[] = {-1,0,1,0};
		  int mx[] = {0,-1,0,1};
		  int ret = 1;
		  for(int i=0;i<4;i++){
			    int ny = y + my[i], nx = x + mx[i];
			    if(0<=ny&&ny<h&&0<=nx&&nx<w && v[ny][nx] == '.'){
			      v[ny][nx] = '#';
			      ret += dfs(ny, nx, v);
			    }
		  }
		  return ret;
	}
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true){
			w = sc.nextInt();
			h = sc.nextInt();
			if(w+h==0)break;
			String[] str = new String[h];
			for(int i=0;i<h;i++){
				str[i] = sc.next();
				for(int j=0;j<w;j++){
					map[i][j] =str[i].charAt(j);
				}					
			}
			for(int i=0;i<h;i++){
				for(int j=0;j<w;j++){
					if(map[i][j]=='@')System.out.println(dfs(i,j,map));
				}
			}
		}
		
	}

}