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<cstdio>
#include<algorithm>
using namespace std;
int nx[]={0,1,0,-1};
int ny[]={-1,0,1,0};
int w,h;
char mp[101][101];
int dfs(int y,int x);
int a,b;
int main()
{
  while(1){
    cin >> w >> h;
    if(w==0&&h==0){
      break;
    }
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	cin >> mp[i][j];
	if(mp[i][j]=='@'){
	  a=i;
	  b=j;
	}
      }
    }
    cout << dfs(a,b) << endl;
  }
  return(0);
}

int dfs(int y,int x){
  if(0>y||0>x||y>=h||x>=w){
    return(0);
  }
  if(mp[y][x]=='#'){
    return(0);
  }
  mp[y][x]='#';
  int ans=0;
  for(int i=0;i<4;i++){
    ans=ans+dfs(y+ny[i],x+nx[i]);
  }
  return ans+1;
}