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 count;//BÂ\È^C
    static int w;//xûüÌ·³
    static int h;//yûüÌ·³

    public static void main(String[] args){
	Scanner sc = new Scanner(System.in);

	w = sc.nextInt();//x
	h = sc.nextInt();//y

	while(w!=0 && h!=0){
	    count = 0;
	    char[][] tile = new char[h][w];//^Cð»ÌÜÜi[
	    int[][] pass = new int[h][w];//Êßµ½ÚóB0(ÊÁÄÈ¢)Æ1(ÊÁ½)ÅL^
	    int posX = 0;//»ÝnÌxÀW
	    int posY = 0;//»ÝnÌyÀW
	    //^Cú»
	    for(int i=0; i<h; i++){
		String line = sc.next();//êsÇÝñÅ©ç
		for(int j=0; j<w; j++){
		    tile[i][j] = line.charAt(j);
		    if(tile[i][j]=='@'){//»ÝÊuðL^
			posX = j;
			posY = i;
		    }
		}
	    }
	    solve(tile,pass,posX,posY);
	    System.out.println(count);
	    
	    w = sc.nextInt();
	    h = sc.nextInt();
	}
    }

    public static void solve(char[][] tile, int[][] pass,int posX, int posY){
	if(pass[posY][posX]==0){//Êßµ½Úó
	    pass[posY][posX] = 1;
	    count++;
	}else return;//ÊßµÄ½çreturn

	if(posY-1>=0 && tile[posY-1][posX]=='.'){//ãûü
	    solve(tile,pass,posX,posY-1);
	}
	if(posX+1<=w-1 && tile[posY][posX+1]=='.'){//Eûü
	    solve(tile,pass,posX+1,posY);
	}
	if(posY+1<=h-1 && tile[posY+1][posX]=='.'){//ºûü
	    solve(tile,pass,posX,posY+1);
	}
	if(posX-1>=0 && tile[posY][posX-1]=='.'){//¶ûü
	    solve(tile,pass,posX-1, posY);
	}

	return;
    }
}