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 i,j,w,h;
string tile[21];
int cnt=0;
int result=0;
int si,sj;

void rec(int i,int j){
  if(tile[i][j]=='.'){
    tile[i][j]='#';
    cnt++;
  }

  if(i+1 < h && tile[i+1][j]=='.')  rec(i+1,j);
  if(j+1 <w && tile[i][j+1]=='.')  rec(i,j+1);
  if(j-1 >=0 && tile[i][j-1]=='.')  rec(i,j-1);
  if(i-1 >=0 && tile[i-1][j]=='.' )  rec(i-1,j);
}

int main(){

  while(1){
    cnt=0;
    result=0;
  cin >> w >> h;
  if(w==0 && h==0)break;
  for(i = 0; i < h; i++){
    cin >> tile[i];
    for(j = 0; j < w; j++){
     
      if(tile[i][j]=='@'){
	si=i;
	sj=j;
      }
    }
  }
 
  rec(si,sj);
 
 
  cout << cnt+1 << endl;
  }
  return 0;
}