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 boolean[][] black;
	static int[][] count;
	static int W, H;

	public static void main(String[] args) {

		Scanner s = new Scanner(System.in);

		while (true) {
			W = s.nextInt();
			H = s.nextInt();

			if (W == 0 && H == 0)
				break;

			char[][] field = new char[H][W];
			black = new boolean[H][W];
			count = new int[H][W];

			for (int i = 0; i < H; i++) {
				String str = s.next();
				field[i] = str.toCharArray();
			}

			int x = 0, y = 0;

			for (int i = 0; i < H; i++) {
				for (int j = 0; j < W; j++) {
					if (field[i][j] == '.')
						black[i][j] = true;
					else if (field[i][j] == '@') {
						black[i][j] = true;
						x = j;
						y = i;
					} else
						black[i][j] = false;
				}
			}

			Search(x, y);

			// for (int i = 0; i < H; i++) {
			// for (int j = 0; j < W; j++) {
			// // System.out.print(field[i][j]);
			// System.out.print(black[i][j]);
			// }
			// System.out.println();
			// }

			int ans = 0;

			for (int i = 0; i < H; i++) {
				for (int j = 0; j < W; j++) {
					ans += count[i][j];
				}
			}

			System.out.println(ans);

		}
		s.close();
	}

	public static void Search(int x, int y) {
		int[] dx = { 1, 0, -1, 0 };
		int[] dy = { 0, 1, 0, -1 };

		black[y][x] = false;
		count[y][x] = 1;

		for (int i = 0; i < dx.length; i++) {
			int sx = x + dx[i];
			int sy = y + dy[i];

			if (sx < W && sy < H && sx >= 0 && sy >= 0)
				if (black[sy][sx])
					Search(sx, sy);
		}
	}
}