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 <algorithm>

#define range(i,a,b) for(int (i)=a;(i)<(b);(i)++)
#define rep(i,n) range(i,0,n)

using namespace std;

char table[30][30];

int dw[4]={1,0,-1,0};
int dh[4]={0,1,0,-1};

void dfs(int w,int h){
	table[h][w]='@';
	rep(i,4){
		int nw=w+dw[i];
		int nh=h+dh[i];
		if(table[nh][nw]=='.')
			dfs(nw,nh);
	}
}

int main(void){
	int w,h;
	while(cin >> w >> h,w|h){
		int sw,sh;
		rep(i,30)rep(j,30) table[i][j]='#';
		range(i,1,h+1) range(j,1,w+1){
			cin >> table[i][j];
			if(table[i][j]=='@'){
				sh=i;
				sw=j;
			}
		}
		dfs(sw,sh);
		int ans=0;
		range(i,1,h+1) range(j,1,w+1) if(table[i][j]=='@') ans++;
		cout << ans << endl;
	}
	return 0;
}