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.util.Arrays;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

public class Main {
  Scanner sc;

  void run() {
    for (; ; ) {
      int W = ni();
      int H = ni();

      if ( (W | H) == 0 ) break;

      boolean[][] field = new boolean[ H + 2 ][ W + 2 ];

      int sx = 0;
      int sy = 0;
      for ( int i = 1; i <= H; ++i ) {
        char[] str = sc.next().toCharArray();
        for ( int j = 1; j <= W; ++j ) {
          if ( str[ j - 1 ] == '@' ) {
            sx = j;
            sy = i;
          }
          if ( str[ j - 1 ] == '.' ) {
            field[ i ][ j ] |= true;
          }
        }
      }

      int cnt = 1;
      Queue<Integer> qx = new LinkedList<Integer>();
      Queue<Integer> qy = new LinkedList<Integer>();
      qx.add(sx);
      qy.add(sy);
      boolean[][] done = new boolean[ H + 2 ][ W + 2 ];
      done[ sy ][ sx ] = true;
      while ( qx.size() > 0 ) {
        int x = qx.poll();
        int y = qy.poll();

        for ( int[] d : ofs ) {
          int nx = x + d[ 0 ];
          int ny = y + d[ 1 ];
          if ( !done[ ny ][ nx ] && field[ ny ][ nx ] ) {
            done[ ny ][ nx ] |= true;
            qx.add(nx);
            qy.add(ny);
            ++cnt;
          }
        }
      }

      System.out.println(cnt);
    }
  }

  int[][] ofs = new int[][]{
      { 0, 1 },
      { 1, 0 },
      { -1, 0 },
      { 0, -1 }
  };

  Main() {
    sc = new Scanner(System.in);
  }

  int ni() {
    return sc.nextInt();
  }

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

  void debug(Object... os) {
    System.err.println(Arrays.deepToString(os));
  }
}