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 <cstring>
using namespace std;

char s[32][32];
int cnt;
int dx[4] = {0,0,1,-1};
int dy[4] = {1,-1,0,0};

void dfs(int y, int x)
{
	cnt++;
	s[y][x]=0;
	for(int i=0; i<4; i++)
	{
		int ny=y+dy[i];
		int nx=x+dx[i];
		if(s[ny][nx]=='.')
			dfs(ny,nx);
	}
}

int main()
{
	int w,h;
	while(cin >> w >> h, w||h)
	{
		cnt = 0;
		memset(s,0,sizeof(s));
		for(int i=1; i<=h; i++)
		{
			cin >> s[i]+1;
		}

		for(int i=1; i<=h; i++)
		for(int j=1; j<=w; j++)
		if(s[i][j]=='@')
		{
			dfs(i,j);
			break;
		}
		cout << cnt << endl;
	}
}