#include <iostream>
#include <string>
using namespace std;

string line[30];
int w, h, x, y, sum;

void countup(int x, int y){
	if(line[y][x] != '#'){
		line[y][x] = '#';
		countup(x,y-1);
		countup(x,y+1);
		countup(x+1,y);
		countup(x-1,y);
		sum++;
	}
	return;
}

int main(){
	while(cin >> w >> h){
		if (!w && !h) break;
		sum = 0;
		for(int i = 1;i<=h;i++){
			cin >> line[i];
			line[i] = "#" + line[i] + "#";
			for(int j = 0;j<=w+1;j++){
				if(line[i][j] == '@'){
					x = j;
					y = i;
				}
			}
		}
		line[h + 1] = line[0] = "#####################";
		countup(x, y);
		cout << sum << endl;
	}
	return 0;
}
### Prompt

In cpp, your task is to solve the following 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

### Response

```cpp
#include <iostream>
#include <string>
using namespace std;

string line[30];
int w, h, x, y, sum;

void countup(int x, int y){
	if(line[y][x] != '#'){
		line[y][x] = '#';
		countup(x,y-1);
		countup(x,y+1);
		countup(x+1,y);
		countup(x-1,y);
		sum++;
	}
	return;
}

int main(){
	while(cin >> w >> h){
		if (!w && !h) break;
		sum = 0;
		for(int i = 1;i<=h;i++){
			cin >> line[i];
			line[i] = "#" + line[i] + "#";
			for(int j = 0;j<=w+1;j++){
				if(line[i][j] == '@'){
					x = j;
					y = i;
				}
			}
		}
		line[h + 1] = line[0] = "#####################";
		countup(x, y);
		cout << sum << endl;
	}
	return 0;
}
```