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 {
    private static boolean[][] fld;

    public static void main(String[] args) {
        try(Scanner scn = new Scanner(System.in)) {
            int w = 0;
            int h = 0;
            int y = 0;
            int x = 0;
            while((w = scn.nextInt()) > 0 | (h = scn.nextInt()) > 0) {
                fld = new boolean[h][w];
                for(int i = 0; i < h; i++) {
                    char[] ary = scn.next().toCharArray();
                    for(int j = 0; j < w; j++) {
                        switch(ary[j]) {
                            case '@':
                                y = i;
                                x = j;
                            case '.':
                                fld[i][j] = true;
                                break;
                            case '#':
                                fld[i][j] = false;
                                break;
                            default:
                                assert false;
                        }
                    }
                }
                System.out.println(count(y, x));
            }
        }
    }

    public static int count(int y, int x) {
        int rslt = 0;
        try {
            if(fld[y][x]) {
                fld[y][x] = false;
                rslt += count(~-y, x);
                rslt += count(y, ~-x);
                rslt += count(y, -~x);
                rslt += count(-~y, x);
                rslt++;
            }
        } catch(ArrayIndexOutOfBoundsException ignore) {}
        return rslt;
    }
}