Description

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) 

 

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).

 

Sample Input

6 9

....#.

.....#

......

......

......

......

......

#@...#

.#..#.

11 9

.#.........

.#.#######.

.#.#.....#.

.#.#.###.#.

.#.#..@#.#.

.#.#####.#.

.#.......#.

.#########.

...........

11 6

..#..#..#..

..#..#..#..

..#..#..###

..#..#..#@.

..#..#..#..

..#..#..#..

7 7

..#.#..

..#.#..

###.###

...@...

###.###

..#.#..

..#.#..

0 0

 

Sample Output

45 59 6 13

 

 

 

 

深搜实现方案：

1 #include
      
        2 #include
       
         3 #include
        
          4 #include
         
           5 using namespace std; 6 char map[110][110]; 7 int  vis[110][100]; 8 int  dir[8][2]={
    {
    0,1},{
    0,-1},{
    1,0},{-1,0}}; 9 int n,m,num;10 void DFS(int x,int y)11 {12     int a,b,i;13     vis[x][y]=1;14     num++;15     for(i=0;i<8;i++)16     {17         a=x+dir[i][0];18         b=y+dir[i][1];19         if(a>=0&&a
          
           =0&&b