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 {
	public static boolean visited[][];
	public static String[][] map;
	static int numberOfBlack;
	
	public static void CheckBlackTiles(int a, int b,int w,int h) {
		numberOfBlack++;
		visited[a][b] = true;
		if(a+1<h && map[a+1][b].equals(".")&& visited[a+1][b]==false) {
			CheckBlackTiles(a+1,b,w,h);
		}
		if(a-1>=0 && map[a-1][b].equals(".")&& visited[a-1][b]==false) {
			CheckBlackTiles(a-1,b,w,h);
		}
		if(b+1<w && map[a][b+1].equals(".") && visited[a][b+1]==false) {
			CheckBlackTiles(a,b+1,w,h);
		}
		if(b-1>=0 && map[a][b-1].equals(".") && visited[a][b-1]==false) {
			CheckBlackTiles(a,b-1,w,h);
		}
	}
	
	public static void main(String args[]) {
		Scanner in = new Scanner(System.in);
		int w;
		int h;
		
		while(true) {
			w = in.nextInt();
			h = in.nextInt();
			if(w==0||h==0) {
				break;
			}
			
			numberOfBlack=0;
			map = new String[h][w];
			visited = new boolean[h][w];

			
			for(int i=0; i<h;i++){    
                String buffer=in.next();
                //文字列格納後に1文字ずつ分離
                for(int l=0; l<buffer.length();l++) {
                	map[i][l]= String.valueOf(buffer.charAt(l));
                	visited[i][l]= false;
                }
			}

			for(int i=0; i<h;i++){
                for(int k=0; k<w;k++){
                	if(map [i][k].equals("@")&&visited[i][k]==false){
                		CheckBlackTiles(i,k,w,h);
                    }
                }      
			}
			System.out.println(numberOfBlack);
		}
		in.close();
	}
}