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;

/**
 * Created by Reopard on 2014/05/29.
 */
public class Main {

    static Scanner sc = new Scanner(System.in);
    static char[][] tile;
    static char black_tile = '.', red_tile = '#', player_tile = '@';
    static int W = 0, H = 0;

    public static void main(String args[]) {
        int x = 0, y = 0;
        while ((W = sc.nextInt()) != 0 && (H = sc.nextInt()) != 0) {
            tile = new char[H+2][W+2];
            for (int i = 0; i <= W + 1; i++) tile[0][i] = red_tile;
            for (int i = 1; i <= H; i++) tile[i] = (red_tile + sc.next() + red_tile).toCharArray();
            for (int i = 0; i <= W + 1; i++) tile[H + 1][i] = red_tile;
            outer:
            for (int i = 1; i <= H; i++) {
                for (int j = 1; j <= W; j++) {
                    if (tile[i][j] == player_tile) {
                        x = j;
                        y = i;
                        break outer;
                    }
                }
            }
            /*for (int i = 0; i <= H+1; i++){
                for(int j = 0; j <= W+1; j++){
                    System.out.print(tile[i][j]);
                }
                System.out.println();
            }
            System.out.println(tile[y][x]);*/
            System.out.println(countBlackTile(x, y));
        }
    }

    static int countBlackTile(int x, int y) {
        int[] dx = {0, 1, 0, -1};
        int[] dy = {-1, 0, 1, 0};
        int count = 1;
        if (tile[y][x] == red_tile) return 0;
        else {
            tile[y][x] = red_tile;
            for(int i = 0; i < 4; i++) {
                count += countBlackTile(x + dx[i], y + dy[i]);
            }
        }
        return count;
    }
}