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 Scanner sc;

    static int n,m;
    static boolean[][] ss;
    static int cnt;

    public static void main(String[] args) {
        sc = new Scanner(System.in);

        // ?????????????§???????
        String[] a;
        while(true) {
            a = GetSubStringLine();
            m = Integer.parseInt(a[0]);
            n = Integer.parseInt(a[1]);
            if (m == 0 && n == 0) {
                break;
            }
            ss = new boolean[n][m];
            int x = 0,y = 0;
            cnt = 0;
            for (int i=0;i<n;i++) {
                String sss = sc.nextLine();
                for (int j=0;j<sss.length();j++) {
                    switch (sss.charAt(j)) {
                        case '.':
                            ss[i][j] = true;
                            break;
                        case '#':
                            ss[i][j] = false;
                            break;
                        case '@':
                            ss[i][j] = true;
                            x = j;
                            y = i;
                            break;
                    }
                }
            }
            dfs(y,x);
            System.out.println(cnt);
        }
    }

    static void dfs(int y, int x) {
        if (y < 0 || y >= n || x < 0 || x>= m) {
            return;
        }
        if (!ss[y][x]) {
            return;
        }
        ss[y][x] = false;
        cnt++;
        dfs(y-1,x);
        dfs(y,x-1);
        dfs(y+1,x);
        dfs(y,x+1);
    }

    public static String[] GetSubStringLine() {
        String s = sc.nextLine();
        return s.split(" ");
    }
}