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<cstring>
#include<algorithm>
using namespace std;
int w,h;
char fie[23][23];
int check[23][23];
int dx[]={0,1,0,-1};
int dy[]={1,0,-1,0};

int solve(int x,int y){
  int ret=1;
  check[x][y]=1;
  for(int i=0;i<4;i++){
    if(x+dx[i] < 0 || x+dx[i] >= w || y+dy[i] <0 || y+dy[i] >=h) continue;
    if(fie[x+dx[i]][y+dy[i]]=='.' && check[x+dx[i]][y+dy[i]]==0){
      ret+=solve(x+dx[i],y+dy[i]);
    }
  }
  return ret;
}

int main(){
  while(1){
    int x,y;
    cin >> w>>h;
    if(!w || !h) break;
    memset(check,0,sizeof(check));
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	cin >> fie[j][i];
	if(fie[j][i]=='@'){ x=j;y=i;}
      }
    }
    cout << solve(x,y) << endl;
  }

}