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 <string>
#include <algorithm>
#include <vector>
#include <utility>
#include <cstring>
using namespace std;

#define rep(i,n) for(int i=0; i<n; i++)
typedef long long ll;

int w, h;
string mp[20];

int dfs(int x, int y) {
	int res = 1;
	mp[y][x] = '#';
	int dx[4] = {-1, 0, 1, 0};
	int dy[4] = { 0,-1, 0, 1};
	rep(i, 4) {
		int nx = x + dx[i];
		int ny = y + dy[i];
		if(0<=nx && nx<w && 0<=ny && ny<h && mp[ny][nx]=='.') {
			res += dfs(nx, ny);
		}
	}
	return res;
}

int main() {
	while(cin >> w >> h, w||h) {
		int sx, sy;
		rep(i, h) {
			cin >> mp[i];
			rep(j, w) {
				if(mp[i][j] == '@') {
					sx = j;
					sy = i;
				}
			}
		}
		cout << dfs(sx, sy) << endl;
	}
	return 0;
}