#include<iostream>
#include<string>
using namespace std;
int ans,w,h,f;
string m[25];
void solve(int x,int y){
  if(x<0 || y<0 || x>=h || y>=w) return;
  if(m[x][y]=='#') return;
  m[x][y]='#';
  ans++;
  solve(x+1,y);
  solve(x-1,y);
  solve(x,y+1);
  solve(x,y-1);
}
int main(void){
  for(;;){
    cin >> w >> h;
    if(!w && !h) break;
    for(int i=0;i<h;i++) cin >> m[i];
    ans=0;
    f=0;
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	if(m[i][j]=='@'){
	  solve(i,j);
	  f=1;
	  break;  
	}
      }
      if(f) break;
    }
    cout << ans << endl;
  }
}

### Prompt

Your task is to create a CPP solution to the following 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

### Response

```cpp
#include<iostream>
#include<string>
using namespace std;
int ans,w,h,f;
string m[25];
void solve(int x,int y){
  if(x<0 || y<0 || x>=h || y>=w) return;
  if(m[x][y]=='#') return;
  m[x][y]='#';
  ans++;
  solve(x+1,y);
  solve(x-1,y);
  solve(x,y+1);
  solve(x,y-1);
}
int main(void){
  for(;;){
    cin >> w >> h;
    if(!w && !h) break;
    for(int i=0;i<h;i++) cin >> m[i];
    ans=0;
    f=0;
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	if(m[i][j]=='@'){
	  solve(i,j);
	  f=1;
	  break;  
	}
      }
      if(f) break;
    }
    cout << ans << endl;
  }
}

```