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:
(lambda f:f(f))(lambda T,A=lambda L,yp,ri=lambda l:R.append([{xi:x}for xi,x in enumerate(l)]):[P.__setitem__("x",L.index("@")),P.__setitem__("y",yp),ri(L)]if "@"in L else ri(L),S=lambda X,Y,s,u:[R[Y][X].__setitem__(X,"@"),s(X-1,Y,s,u)+s(X+1,Y,s,u)+s(X,Y+1,s,u)+s(X,Y-1,s,u)+1][1]if 0<=X<W[0]and 0<=Y<W[1]and u(X,Y)else 0,u=lambda X,Y:R[Y][X].get(X)is ".",g=globals:[g().__setitem__("W",list(map(int,input().split()))),g().__setitem__("R",[]),g().__setitem__("P",{"x":9,"y":9}),[A(input(),Y)for Y in range(W[1])],[R[P["y"]][P["x"]].__setitem__(P["x"],"."),print(S(P["x"],P["y"],S,u)),T(T)]if R else 9])