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>
using namespace std;
int x[21][21],ans=0,w,h;
string d[21];
void f(int i,int j){
	ans++;
	x[i][j]=1;
	if(i+1<h){
		if(x[i+1][j]==0 && d[i+1][j]=='.')
		f(i+1,j);
	}
	if(i-1>=0){
		if(x[i-1][j]==0 && d[i-1][j]=='.')
		f(i-1,j);
	}
	if(j+1<w){
		if(x[i][j+1]==0 && d[i][j+1]=='.')
		f(i,j+1);
	}
	if(j-1>=0){
		if(x[i][j-1]==0 && d[i][j-1]=='.')
		f(i,j-1);
	}
}
int main(){
	while(cin>>w>>h,w){
		int a,b;
		ans=0;
		for(int i=0;i<21;i++){
			for(int j=0;j<21;j++){
				x[i][j]=0;
			}
		}
		for(int i=0;i<h;i++){
			cin>>d[i];
			for(int j=0;j<w;j++){
				if(d[i][j]=='@'){
					a=j;
					b=i;
				}
			}
		}
		f(b,a);
		cout<<ans<<endl;
	}
	return 0;
}