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 final char CHECKED = 'C';
	static final char BLACK = '.';
	static final char START = '@';
	void run(){
		Scanner s = new Scanner(System.in);
		while(true){
			int w = s.nextInt();
			int h = s.nextInt();
			if(w == 0 && h == w)break;
			int x = 0;
			int y = 0;
			char tile[][] = new char[h][w];
			for(int i = 0;i < h;i++){
				String row = s.next();
				for(int j = 0;j < w;j++){
					tile[i][j] = row.charAt(j);
					if(tile[i][j] == START){
						y = i;
						x = j;
						tile[i][j] = BLACK;
					}
				}
			}
			System.out.println(cntTile(tile,y,x));
		}
	}

	int cntTile(char[][] panel,int y,int x){
		//??????????????´??????????????\????????¢?´¢???????????????0????????´?????????
		if(y >= panel.length)return 0;
		if(y < 0)return 0;
		if(x >= panel[0].length)return 0;
		if(x < 0)return 0;
		int cnt = 0;
		if(panel[y][x] == BLACK){
			panel[y][x] = CHECKED;
			cnt++;
			//??±???????????¢?´¢????????????????????¢?´¢??????????????°?????????
			cnt += cntTile(panel,y + 1,x);
			cnt += cntTile(panel,y - 1,x);
			cnt += cntTile(panel,y,x + 1);
			cnt += cntTile(panel,y,x - 1);
			return cnt;
		}else{
			return 0;
		}
	}

public static void main(String args[]){
		new Main().run();
	}
}