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 PYTHON3):

Solution:
dxy = [(1, 0), (0, 1), (-1, 0), (0, -1)]
def rec(maze, visited, locat):
  # ４方向全て試す
  for i in dxy:
    n_locat = (locat[0] + i[0], locat[1] + i[1])
    if 0 <= n_locat[0] < len(maze) and 0 <= n_locat[1] < len(maze[0]):
      if maze[n_locat[0]][n_locat[1]] == '.':
        if visited[n_locat[0]][n_locat[1]] == False:
          global count 
          count += 1
          visited[n_locat[0]][n_locat[1]] = True
          rec(maze, visited, n_locat)
  return count
while(True):
  w, h = map(int, input().split())
  if w == 0 and h == 0:
    break
  maze = [[]for i in range(h)]
  visited = [[False for i in range(w)] for j in range(h)]
  for i in range(h):
    mazel = list(input())
    maze[i] = mazel
  count = 1 # @のいちを予めカウントしておく
  for i in range(h):
    for j in range(w):
      if maze[i][j] == '@':
        s = [i, j]
        break
    else:
      continue
    break
  print(rec(maze, visited, s))