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 <string.h>
#include <cmath>
using namespace std;

int main(){

    int c[21][21],w,h;
    memset(c,0,sizeof(c));
    char t;
    while(1){
    cin>>w>>h;if(w==0&&h==0)return 0;
    for(int i=0;i<w*h;i++){cin>>t;c[i%w][i/w]=t;}
    for(int i=0;i<w*h;i++){
      for(int j=0;j<w*h;j++)
        if(c[j%w][j/w]==64){
	  if(c[j%w-1][j/w]==46)c[j%w-1][j/w]=64;
          if(c[j%w+1][j/w]==46)c[j%w+1][j/w]=64;
          if(c[j%w][j/w-1]==46)c[j%w][j/w-1]=64;
          if(c[j%w][j/w+1]==46)c[j%w][j/w+1]=64;
        }
    }
    int cou=0;
    for(int i=0;i<w*h;i++)if(c[i%w][i/w]==64)cou++;
    cout<<cou<<endl;
    } 
}