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.Arrays;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		StringBuilder sb = new StringBuilder();
		while (in.hasNext()) {
			int w = in.nextInt();
			int h = in.nextInt();
			if (w != 0 && h != 0) {
				char[][] tile = new char[h + 2][];
				int fx = -1;
				int fy = -1;
				tile[0] = new char[w + 2];
				Arrays.fill(tile[0], '#');
				for (int y = 0; y < h; y++) {
					sb.setLength(0);
					sb.append('#').append(in.next()).append('#');
					String line = sb.toString();
					tile[y + 1] = line.toCharArray();
					if (line.contains("@")) {
						fy = y + 1;
						fx = line.indexOf('@');
					}
				}
				tile[h + 1] = new char[w + 2];
				Arrays.fill(tile[h + 1], '#');
				tile[fy][fx] = '.';
				fill(fx, fy, tile);
				int count = 0;
				for (char[] l : tile) {
					for (char c : l) {
						if (c == '@') count++;
					}
				}
				System.out.println(count);
			} else {
				break;
			}
		}
	}

	private static void fill(int fx, int fy, char[][] tile) {
		if (tile[fy][fx] == '.') {
			tile[fy][fx] = '@';
			fill(fx + 1, fy, tile);
			fill(fx - 1, fy, tile);
			fill(fx, fy + 1, tile);
			fill(fx, fy - 1, tile);
		}
	}
}