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>
#define REP(i,s,n) for(int i=s ; i < n ; i++)
#define rep(i,n) REP(i,0,n)
using namespace std;

int W,H;
char field[20][20];
int cnt;

void dfs(int x,int y){

  field[y][x]='#';
  
  cnt++;
  
  if( x+1 < W && field[y][x+1] == '.'){
    dfs(x+1,y);
  }
  if(x-1 >= 0 && field[y][x-1] == '.'){
    dfs(x-1,y);
  }
  if(y+1 < H && field[y+1][x] == '.'){
    dfs(x,y+1);
  }
  if(y-1 >=0 && field[y-1][x] == '.'){
    dfs(x,y-1);
  }
  
}
int main(){
  
  int x,y;
  
  while(1){
    cin >>W>>H;
    if(W==0 && H==0)break;
    
    rep(i,H){
      rep(j,W){
	cin >>field[i][j];
	if(field[i][j] == '@'){
	  x=j;
	  y=i;
	}
      }
    }
    cnt=0;
    dfs(x,y);
    cout <<cnt<<endl; 
  }
  
  return 0;
}