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.*;

public class Main {
    public static boolean[][] visited;
    public static char[][] map;
    public static int[] moveR = {0,0,1,-1};
    public static int[] moveC = {-1,1,0,0};
    public static int R;
    public static int C;
    
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        // int TC = Integer.parseInt(sc.next(), 10);
        
        while (true) {
            C = sc.nextInt();
            R = sc.nextInt();
            if (C == 0 && R == 0) break;
            
            int rPos = -1;
            int cPos = -1;
            visited = new boolean[R][C];
            
            map = new char[R][C];
            for (int r = 0; r < R; r++) {
                String line = sc.next();
                for (int c = 0; c < C; c++) {
                    map[r][c] = line.charAt(c);
                    if (map[r][c] == '@') {
                        rPos = r;
                        cPos = c;
                    }
                }
            }
            
            System.out.println(floodFill(rPos, cPos));
        }
    }
    
    public static int floodFill(int r, int c) {
        if (r < 0 || r >= R || c < 0 || c >= C) return 0;
        if (visited[r][c] || map[r][c] == '#') return 0;
        visited[r][c] = true;
        int ret = 1;
        for (int m = 0; m < 4; m++) {
            ret += floodFill(r + moveR[m], c + moveC[m]);
        }
        return ret;
    }
}