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.*;

class Main{
	static int a,b;
	static int ans=0;
	static int[][] takeshi;
	public static void main(String args[]){
		Scanner s=new Scanner(System.in);
		
		while(true){
			b=s.nextInt();
			a=s.nextInt();
			if(a==0)System.exit(0);
			takeshi=new int[a][b];
			String now;
			int p=0,q=0;
			for(int i=0;i<a;i++){
				now=s.next();
				for(int j=0;j<b;j++){
					if(now.charAt(j)=='#')takeshi[i][j]=0;
					else if(now.charAt(j)=='.')takeshi[i][j]=1;
					else{
						takeshi[i][j]=0;
						p=i;
						q=j;
					}
				}
			}
			
			
			System.out.println(solve(p,q));
		}
	}
	static int solve(int m,int n){
		int ret=0;
		
		takeshi[m][n]=0;
		
		if(m>0)
			if(takeshi[m-1][n]==1)ret+=solve(m-1,n);
		if(m<a-1)
			if(takeshi[m+1][n]==1)ret+=solve(m+1,n);
		if(n>0)
			if(takeshi[m][n-1]==1)ret+=solve(m,n-1);
		if(n<b-1)
			if(takeshi[m][n+1]==1)ret+=solve(m,n+1);
		
		
		return ret+1;
	}
}