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:
def fill(y,x):
    global l,c,w,h
    if 0<=x+1<w and 0<=y<h and l[y][x+1]==".":
        c+=1
        l[y][x+1]=1
        fill(y,x+1)
    if 0<=x-1<w and 0<=y<h and l[y][x-1]==".":
        c+=1
        l[y][x-1]=1
        fill(y,x-1)
    if 0<=x<w and 0<=y+1<h and l[y+1][x]==".":
        c+=1
        l[y+1][x]=1
        fill(y+1,x)
    if 0<=x<w and 0<=y-1<h and l[y-1][x]==".":
        c+=1
        l[y-1][x]=1
        fill(y-1,x)
    return c

while 1:
    w,h=map(int,input().split())
    if not w and not h:break
    l=[list(input()) for _ in range(h)]
    y,x=[[n,i.index("@")] for (n,i) in enumerate(l) if "@" in i][0]
    l[y][x]=1
    c=1
    print(fill(y,x))