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<algorithm>
#include<vector>

using namespace std;

int xs[] = {0, 1, 0, -1}, ys[] = {1, 0, -1, 0};
char c[108][108];
int w, h;
bool come[108][108];
int dfs(int x, int y){
	if(x < 0 || y < 0 || x >= h || y >= w)return 0;
	if(c[x][y] == '#')return 0;
	if(come[x][y])return 0;
	come[x][y] = true;
	int res = 1;
	for(int i = 0;i < 4;i++){
		res += dfs(x + xs[i], y + ys[i]);
	}
	return res;
}

int main(){
	int si, sj;
	while(cin >> w >> h, w | h){
		for(int i = 0;i < h;i++){
			for(int j = 0;j < w;j++){
				cin >> c[i][j];
				if(c[i][j] == '@'){
					si = i;
					sj = j;
				}
				come[i][j] = false;
			}
		}
		cout << dfs(si, sj) << endl;
	}
	return 0;
}