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<vector>
using namespace std;

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

int dfs(int y, int x, vector<string> &g){
  if(g[y][x] == '#')return 0;
  g[y][x] = '#';

  int res = 1;
  for(int i=0;i<4;i++){
    int ny = y + dy[i], nx = x + dx[i];
    if(ny<0 || nx<0 || ny>=(int)g.size() || nx>=(int)g[0].size())continue;
    res += dfs(ny,nx,g);
  }
  return res;
}

int main(){
  int w,h;
  while(cin >> w >> h){
    if(w==0 && h==0)break;

    vector<string> g(h);
    int y=0,x=0;
    for(int i=0;i<h;i++){
      cin >> g[i];
      for(int j=0;j<w;j++){
	if(g[i][j] == '@')y = i, x = j;
      }
    }

    cout << dfs(y,x,g) << endl;
  }
}