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 static java.lang.System.*;

class Main {
	public static Scanner sc = new Scanner(in);
	public static Random rand=new Random();

	static class P{
		int x;
		int y;
		public P(int x,int y){
			this.x=x;this.y=y;
		}

		@Override
		public boolean equals(Object obj) {
			if(!(obj instanceof P))return false;
			P p=(P)obj;
			return p.x==x && p.y==y;
		}
		@Override
		public String toString() {
			return "("+x+","+y+")";
		}
	}

	public void run() {
		Test:while(true){
			int w=sc.nextInt(),h=sc.nextInt();
			if(w==0 && h==0)return;
			boolean[][] wall=new boolean[h][w];
			Queue<P> pq=new LinkedList<P>();
			for(int i=0;i<h;i++){
				char[] mc=sc.next().toCharArray();
				for(int j=0;j<w;j++){
					switch(mc[j]){
					case '#':
						wall[i][j]=true;
						break;
					case '@':
						wall[i][j]=true;
						pq.offer(new P(j,i));
					}
				}
			}

			int res=1;

			int[][] d=new int[][]{{0,1},{1,0},{0,-1},{-1,0}};
			while(!pq.isEmpty()){
				P p=pq.poll();
				for(int i=0;i<4;i++){
					int x=p.x+d[i][0];
					int y=p.y+d[i][1];
					if(0<=x && x<w && 0<=y && y<h){
						if(!wall[y][x]){
							wall[y][x]=true;
							res++;
							pq.add(new P(x,y));
						}
					}
				}
			}
			ln(res);
		}
	}
	public static void main(String[] args) {
		new Main().run();
	}

	public int[] nextIntArray(int n){
		int[] res=new int[n];
		for(int i=0;i<n;i++){
			res[i]=sc.nextInt();
		}
		return res;
	}
	public static void pr(Object o) {
		out.print(o);
	}
	public static void ln(Object o) {
		out.println(o);
	}
	public static void ln() {
		out.println();
	}
}