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>
using namespace std;

char c[25][25];
void dfs(int x,int y,int w,int h) {
	c[x][y] = '!';

	for (int i = -1;i <= 1;i++) {
		int ax = x + i;
		if (ax >= 0 && ax < h&&c[ax][y] == '.')dfs(ax, y, w, h);
	}
	for (int i = -1;i<= 1;i++) {
		int ay = y + i;
		if (ay >= 0 && ay < w&&c[x][ay] == '.')dfs(x, ay, w, h);
	}
}

int main() {
	int w, h;
	while (cin >> w >> h,w,h) {
		for (int i = 0;i < h;i++) {
			for (int j = 0;j < w;j++)cin >> c[i][j];
		}

		for (int i = 0;i < h;i++) {
			for (int j = 0;j < w;j++) {
				if (c[i][j] == '@')dfs(i,j,w,h);
			}
		}
		int al = 0;
		for (int i = 0;i < h;i++) {
			for (int j = 0;j < w;j++) {
				if (c[i][j] == '!')al++;
			}
		}
		cout << al << endl;
	}
	return 0;
}