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 CPP):

Solution:
#include<cstdio>
#include<iostream>
using namespace std;

char **data;
int w,h;

int r(int,int);

int main(){
	int i,j;
	int num;
	int x,y;
	while(cin>>w>>h){
		if(w==0 && h==0) break;
		data=new char*[h];
		for(i=0;i<h;i++){
			data[i]=new char[w+1];
			cin>>data[i];
			for(j=0;j<w;j++){
				if(data[i][j]=='@'){
					data[i][j]='.';
					x=j;
					y=i;
				}
			}
		}
		num=r(x,y);
		cout<<num<<endl;
	}
	return 0;
}

int r(int x,int y){
	int count=0;
	if(x>=w || x<0) return 0;
	if(y>=h || y<0) return 0;

	if(data[y][x]=='.'){
		data[y][x]='@';
		count++;
	}
	else return 0;
	count+=r(x+1,y);
	count+=r(x-1,y);
	count+=r(x,y+1);
	count+=r(x,y-1);
	return count;
}