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:
#2:52
import sys

sys.setrecursionlimit(10000000)


dx = [1, 0, -1, 0]
dy = [0, 1, 0, -1]



#左上からせめて深さ優先で探索する問題
while True:
    # 地図作る
    width,hight = map(int,input().split())
    if width ==0 :
        break
    d =[]
    for _ in range(hight):
        d.append(list(input()))
    
    def dfs(x, y):
    # いまたどり着いたはずなので1に塗りつぶす
        d[y][x]="d"

    #4方向ループ
    #あくまで方向の表し方dxは
        for i in range(4):
            ny = y + dx[i]
            nx = x + dy[i]

        #行ったことがなくって、迷路の範囲内で、障害物がなければ、進む
            if 0 <= ny and ny < hight \
              and 0 <= nx and nx < width \
              and d[ny][nx] == ".":
                dfs(nx,ny) 

    


    for y in range(hight):
        for x in range(width):
            if d[y][x] == "@":
                dfs(x,y)
    
    sum = 0 
    for _ in range(hight):
        sum = sum + d[_].count('d')
    print(sum)