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<iostream>
#include<sstream>
#include<vector>

using namespace std;

vector<string> map;
int w,h,area;
int dx[]={0,0,-1,1};
int dy[]={-1,1,0,0};

void f(int x,int y){
	map[y][x]='#';
	for(int i=0;i<4;i++)
		if(0<=x+dx[i]&&x+dx[i]<w&&0<=y+dy[i]&&y+dy[i]<h)
			if(map[y+dy[i]][x+dx[i]]=='.'){
				area++;
				f(x+dx[i],y+dy[i]);
			}
}

int main(){
	ostringstream out;

	string line;

	while(cin >> w >> h, w|h){
		map.clear();
		int x=-1,y;
		area=1;
		for(int iy=0;iy<h;iy++){
			cin >> line;
			map.push_back(line);
			if(x==-1)
				for(int ix=0;ix<line.length();ix++)
					if(line[ix]=='@'){
						x=ix;
						y=iy;
					}
		}

		f(x,y);

		out << area << endl;
	}


	cout << out.str();
	return 0;
}