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 {	
	String[] tile;
	boolean[][] board;

	void doIt() {
		Scanner stdIn =new Scanner(System.in);

		while(stdIn.hasNext()) {
			Queue<Integer> qx = new LinkedList<Integer>();
			Queue<Integer> qy = new LinkedList<Integer>();

			int width = stdIn.nextInt();
			int height = stdIn.nextInt();
			if(width + height == 0) break;
			tile = new String[height];
			board = new boolean[height][width];
			for(int r = 0; r < height; r++) {
				tile[r] = stdIn.next();
				for(int c = 0; c < width; c++) {
					if(tile[r].charAt(c) == '@') {
						qx.add(c);
						qy.add(r);
						board[r][c] = true;
					}
				}
			}

			int[] fdx = new int[]{1, -1, 0, 0};
			int[] fdy = new int[]{0, 0, -1, 1};
			int count = 1;//既に現在地は訪れているので含めておく
			while(!qx.isEmpty()) {
				int nowx = qx.poll();
				int nowy = qy.poll();
				for(int r = 0; r < fdx.length; r++) {
					int nextx = nowx + fdx[r];
					int nexty = nowy + fdy[r];
					if(!(nextx >= 0 && nexty >= 0 && nextx < width && nexty < height)) continue;
					if(tile[nexty].charAt(nextx) != '#' && !board[nexty][nextx]) {
						qx.add(nextx);
						qy.add(nexty);
						board[nexty][nextx] = true;
						count++;
					}
				}
			}
			System.out.println(count);
		}
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		new Main().doIt();
	}
}