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:
// Red and Black
import java.util.Scanner;

public class Main {
	int w, h;
	String[] field;
	boolean[][] visited;

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

	void run() {
		Scanner sc = new Scanner(System.in);
		while (true) {
			w = sc.nextInt();
			h = sc.nextInt();
			if ((w | h) == 0)
				break;
			field = new String[h];
			visited = new boolean[h][w];
			int result = 0;
			for (int i = 0; i < h; i++)
				field[i] = sc.next();
			for (int i = 0; i < h; i++) {
				for (int j = 0; j < w; j++) {
					if (field[i].charAt(j) == '@') {
						result = visit(j, i);
						break;
					}
				}
			}
			System.out.println(result);
		}
		sc.close();
	}

	int visit(int x, int y) {
		int result = 1;
		visited[y][x] = true;
		if (x > 0 && field[y].charAt(x - 1) != '#' && !visited[y][x - 1])
			result += visit(x - 1, y);
		if (x < w - 1 && field[y].charAt(x + 1) != '#' && !visited[y][x + 1])
			result += visit(x + 1, y);
		if (y > 0 && field[y - 1].charAt(x) != '#' && !visited[y - 1][x])
			result += visit(x, y - 1);
		if (y < h - 1 && field[y + 1].charAt(x) != '#' && !visited[y + 1][x])
			result += visit(x, y + 1);
		return result;
	}
}