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 count, H, W;
	static int[][] move = {{1,0}, {-1,0}, {0,1}, {0,-1}};
	static char[][] r;
	
	static void dfs(int i, int j) {
		for(int k=0; k<4; k++) {
			int ni = i + move[k][0];
			int nj = j + move[k][1];
			if(0<=ni && ni<H && 0<=nj && nj<W && r[ni][nj] != '#') {
				r[ni][nj] = '#';
				count++;
				dfs(ni, nj);
			}
		}
	}
	
	public static void main(String[] args) {
		try(Scanner sc = new Scanner(System.in)) {
			while(sc.hasNext()) {
				W = sc.nextInt();
				H = sc.nextInt();
				if(W+H == 0) break;
				
				r = new char[H][W];
				int si = 0;
				int sj = 0;
				
				for(int i=0; i<H; i++) {
					char[] s = sc.next().toCharArray();
					for(int j=0; j<W; j++) {
						r[i][j] = s[j];
						if(s[j] == '@') {
							si = i;
							sj = j;
						}
					}
				}
				count = 1;
				r[si][sj] = '#';
				dfs(si, sj);
				System.out.println(count);
			}
		}
	}
}