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 JAVA):

Solution:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

public class Main {
	
	int count = 1;
	
	void run() throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] dataSet = br.readLine().split(" ");
		int W = Integer.parseInt(dataSet[0]);
		int H = Integer.parseInt(dataSet[1]);
		
		List<Integer> result = new ArrayList<Integer>();
		
		while (W != 0 || H != 0) {
			int startW = 0;
			int startH = 0;
			char[][] tile = new char[H][W];
			for (int i = 0; i < H; i++) {
				String line = br.readLine();
				for (int j = 0; j < W; j++) {
					tile[i][j] = line.charAt(j);
					if (line.charAt(j) == '@') {
						startW = i; 
						startH = j;
					}
				}
			}
			trace(startW, startH, tile, H, W);
			result.add(count);
			count = 1;
			dataSet = br.readLine().split(" ");
			W = Integer.parseInt(dataSet[0]);
			H = Integer.parseInt(dataSet[1]);
		}
		for (int i = 0; i < result.size(); i++) {
			System.out.println(result.get(i));
		}
	}
	
	void trace(int i, int j, char tile[][], int H, int W) {
		int up = 0;
		int down = 0;
		int right = 0;
		int left = 0;
		
		// ??????????????¢?´¢
		if (i - 1 >= 0) {
			if (tile[i - 1][j] == '.') {
				count++;
				tile[i - 1][j] = '%';
				up = i - 1;
				trace(up, j, tile, H, W);
			}
		}
		// ??????????????¢?´¢
		if (j + 1 < W) {
			if (tile[i][j + 1] == '.') {
				count++;
				tile[i][j + 1] = '%';
				right = j + 1;
				trace(i, right, tile, H, W);
			}
		}
		// ??????????????¢?´¢
		if (i + 1 < H) {
			if (tile[i + 1][j] == '.') {
				count++;
				tile[i + 1][j] = '%';
				down = i + 1;
				trace(down, j, tile, H, W);
			}
		}
		// ??????????????¢?´¢
		if (j - 1 >= 0) {
			if (tile[i][j - 1] == '.') {
				count++;
				tile[i][j - 1] = '%';
				left = j - 1;
				trace(i, left, tile, H, W);
			}
		}
	}

	public static void main(String[] args) throws NumberFormatException, IOException {
		new Main().run();
	}

}