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>
using namespace std;

int tile[22][22];
int sum;

void search(int w,int h)
{
  if(tile[w][h]){
    tile[w][h]=0; sum++;
    search(w,h-1);
    search(w-1,h);
    search(w+1,h);
    search(w,h+1);
  }
}

int main()
{
  int w,h,i,j,sx,sy;
  char c;
  
  for(;;){
    cin>>w>>h;
    if(!(w|h)) break;

    sum=0;
    for(i=0;i<22;i++)
      for(j=0;j<22;j++)
	tile[i][j]=0;
    for(i=1;i<h+1;i++){
      for(j=1;j<w+1;j++){
	cin>>c;
	if(c=='#') tile[j][i]=0;
	else if(c=='.') tile[j][i]=1;
	else if(c=='@'){
	  tile[j][i]=1; sx=j; sy=i;
	}
      }
    }
    search(sx,sy);
    cout<<sum<<endl;
  }
}