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:
x=0
y=0
b=[]
t=[]
dir=[[1,0],[0,1],[-1,0],[0,-1]]
ans=0

def dfs(p_x,p_y):
  global b,t,ans
  if t[p_y][p_x] or not b[p_y][p_x]: return
  ans+=1
  t[p_y][p_x]=True
  for i in dir:
    dfs(p_x+i[0],p_y+i[1])

while True:
  x=0
  y=0
  w,h=map(int,input().split())
  if w==0 and h==0: break
  b=[[False]*(w+2) for i in range(h+2)]
  t=[[False]*(w+2) for i in range(h+2)]
  ans=0
  for i in range(1,h+1):
    tmp=list(input())
    for j in range(1,w+1):
      b[i][j]=(tmp[j-1] in {'.','@'})
      if tmp[j-1]=='@': x=j;y=i
  dfs(x,y)
  print(ans)