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<cstdio>
#include<algorithm>
#include<map>
#include<string>
using namespace std;

const int dy[4] = {-1,0,1,0}, dx[4] = {0,1,0,-1};
int H,W,ans;
char fld[20][20];

void dfs(int y,int x){
    int ny,nx;
    ans++; fld[y][x] = '#';
    for(int i=0;i<4;i++){
        ny = y+dy[i]; nx = x+dx[i];
        if(0<=ny && ny<H && 0<=nx && nx<W && fld[ny][nx]=='.') dfs(ny,nx);
    }
}

int main(){
    int sy,sx;
    while(cin>>W>>H,H||W){
        ans = 0;
        for(int i=0;i<H;i++){
            for(int j=0;j<W;j++){
                cin>>fld[i][j];
                if(fld[i][j]=='@') sy = i, sx = j;
            }
        }
        dfs(sy,sx);
        printf("%d\n",ans);
    }
}