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<cstdio>
#include<iostream>
#include<algorithm>
using namespace std;
int solve(int x,int y);
char room[30][30];
int dx[4]={0,1,0,-1};
int dy[4]={-1,0,1,0};
int w,h;
int main(void){
  int ans;
  while(1){
    scanf("%d %d",&w,&h);
    if(w==0 && h==0) break;
    ans=0;
    for(int i=0;i<h;i++) scanf("%s",room[i]);
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	if(room[i][j]=='@') ans=solve(i,j);
      }
      if(ans)break;
    }
    printf("%d\n",ans);
  }
}

int solve(int x,int y){
  int res=1;
  room[x][y]='#';
  for(int i=0;i<4;i++){
    int nx=x+dx[i];
    int ny=y+dy[i];
    if(0<=nx && nx<h && 0<=ny && ny<w){
      if(room[nx][ny]=='.') res+=solve(nx,ny);
    }
  }
  return res;
}