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 {
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		for(;;){
			String tile[][] = new String[22][22];
			int num = 1;
			int num_before = 0;
			for(int i = 0; i < 22; i++){
				for(int j = 0; j < 22; j++){
					tile[i][j] = "#";
				}
			}
			int W = scan.nextInt();
			int H = scan.nextInt();
			if(W == 0 && H == 0)
				break;
			for(int i = 1; i <= H; i++){
				String tile_row = scan.next();
				for(int j = 0; j < W ; j++){
					tile[i][j + 1] = tile_row.substring(j,j + 1);
				}
			}
			for(int i = 0; i <= W * H; i++){
				for(int j = 1; j <= H; j++){
					for(int l = 1; l <= W; l++){
						if(tile[j][l].equals("@")){
							if(tile[j - 1][l].equals(".")){
								tile[j - 1][l] = "@";
								num++;
							}
							if(tile[j + 1][l].equals(".")){
								tile[j + 1][l] = "@";
								num++;
							}
							if(tile[j][l - 1].equals(".")){
								tile[j][l - 1] = "@";
								num++;
							}
							if(tile[j][l + 1].equals(".")){
								tile[j][l + 1] = "@";
								num++;
							}
						}
					}
				}
				if(num == num_before)
					break;
				num_before =num;
			}
			System.out.println(num);
		}
	}
}