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 <cstdio>
#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;
char heya[22][22];
char vis[22][22];
int H,W;

int solve(int x,int y){
  if(y<0||y>=W) return 0;
  if(x<0||x>=H) return 0;
  if(heya[x][y]!='.') return 0;
  if(vis[x][y]==1) return 0;
  vis[x][y]=1;
  int res=1;
  res+=solve(x+1,y);
  res+=solve(x-1,y);
  res+=solve(x,y+1);
  res+=solve(x,y-1);
  return res;
}

int main(void){
  int i,j;
  int sx,sy;
  while(cin>>W>>H,W||H){
    sx=sy=0;
    for(i=0;i<H;i++){
      for(j=0;j<W;j++){
        cin>>heya[i][j];
        vis[i][j]=0;
        if(heya[i][j]=='@'){
          sx=i;sy=j;
          heya[i][j]='.';
        }
      }
    }
    cout<<solve(sx,sy)<<endl;
  }
  return 0;
}