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.*;
import java.lang.*;
import java.math.*;
import java.io.*;

import static java.lang.Math.*;
import static java.util.Arrays.*;

public class Main {

	Scanner sc = new Scanner(System.in);

	int INF = 1 << 28;
	double EPS = 1e-9;

	int m,n;
	int[][] a;
	int x0,y0;
	
	void run() {
		for(;;){
			m=sc.nextInt();
			n=sc.nextInt();
			if((m|n)==0){
				break;
			}
			a=new int[n][m];
			for(int j=0;j<n;j++){
				String s=sc.next();
				for(int i=0;i<m;i++){
					if(s.charAt(i)=='@'){
						x0=i;
						y0=j;
					}else if(s.charAt(i)=='#'){
						a[j][i]=1;
					}
				}
			}
			solve();
		}
	}

	void solve() {
		LinkedList<P> que=new LinkedList<P>();
		boolean[][] visited=new boolean[n][m];
		int ans=0;
		
		que.offer(new P(x0,y0));
		visited[y0][x0]=true;
		
		int[] dx={0,0,-1,1};
		int[] dy={-1,1,0,0};
		
		for(;!que.isEmpty();){
			P p=que.poll();
			ans++;
			for(int i=0;i<4;i++){
				P q=new P(p.x+dx[i],p.y+dy[i]);
				if(q.x>=0&&q.x<m&&q.y>=0&&q.y<n&&a[q.y][q.x]==0&&!visited[q.y][q.x]){
					que.offer(q);
					visited[q.y][q.x]=true;
				}
			}
		}
		println(ans+"");
	}
	
	class P{
		int x,y;
		P(int x,int y){
			this.x=x;
			this.y=y;
		}
	}

	void debug(Object... os) {
		System.err.println(Arrays.deepToString(os));
	}

	void print(String s) {
		System.out.print(s);
	}

	void println(String s) {
		System.out.println(s);
	}

	public static void main(String[] args) {
		// System.setOut(new PrintStream(new BufferedOutputStream(System.out)));
		new Main().run();
	}
}