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 <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define loop(i,a,b) for(ll i=(a);i<ll(b);i++)
#define rep(i,b) loop(i,0,b)

int h,w;
char g[30][30];

int rec(int ci, int cj){
    g[ci][cj] = '#';
    int ans = 1;
    int di[] = {0,1,0,-1};
    int dj[] = {1,0,-1,0};
    rep(i,4){
        int ni = ci + di[i];
        int nj = cj + dj[i];
        if(ni >= h || nj >= w || ni < 0 || nj < 0 || g[ni][nj] == '#') continue;
        ans += rec(ni,nj);
    }
    return ans;
}

int main(){
    while(scanf("%d%d",&w,&h), w != 0){
        rep(i,h) scanf("%s",g[i]);
        int ans = 0;
        rep(i,h)rep(j,w) if(g[i][j]=='@') ans = rec(i,j);
        printf("%d\n",ans);
    }
}