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>
using namespace std;

int h,w;
string str[30];

int dx[] = {1,-1,0,0};
int dy[] = {0,0,1,-1};

int dfs(int y,int x){
    str[y][x] = '#';
    int res = 0;
    for(int i=0;i<4;i++){
        if(y+dy[i]<0 || y+dy[i]>=h || x+dx[i]<0 || x+dx[i]>=w || str[y+dy[i]][x+dx[i]]!='.') continue;
        res += dfs(y+dy[i],x+dx[i])+1;
    }
    return res;
}

int main()
{
    
    while(cin >> w >> h,w!=0&&h!=0){
        for(int i=0;i<h;i++) cin >> str[i];
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                if(str[i][j] == '@'){
                    cout << dfs(i,j)+1 << endl;
                }
            }
        }
    }

    return(0);
}