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 int c = 0;
    static int[][] directions = {{0, -1}, {0, 1}, {1, 0}, {-1, 0}};
    static int[][] m;

    public static void spreadFrom(int x, int y) {
        if (m[y][x] != 1) {
            m[y][x] = 1;
            c++;
        }

        for (int k = 0; k < 4; k++) {
            int nx = x + directions[k][0];
            int ny = y + directions[k][1];
            if (nx >= 0 && nx < m[y].length && ny >= 0 && ny < m.length && m[ny][nx] == 0) {
                spreadFrom(nx, ny);
            }
        }
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (true) {
            c = 0;
            int W = sc.nextInt();
            int H = sc.nextInt();
            if (W == 0 && H == 0)
                break;
            m = new int[H][W];
            int[] start = new int[2];
            for (int i = 0; i < H; i++) {
                String rowStr = sc.next();
                for (int j = 0; j < W; j++) {
                    int point = 1;
                    switch (Character.toString(rowStr.charAt(j))) {
                        case ".":
                            point = 0;
                            break;
                        case "#":
                            point = 1;
                            break;
                        case "@":
                            point = 2;
                            start[0] = j;
                            start[1] = i;
                            break;
                    }
                    m[i][j] = point;
                }
            }
            spreadFrom(start[0], start[1]);
            System.out.println(c);
        }
    }
}