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 this, atin=lambda line, yp, ri=lambda l: room.append([{xi: x} for xi, x in enumerate(l)]): [point.__setitem__("x", line.index("@")), point.__setitem__("y", yp), ri(line)] if "@" in line else ri(line), search=lambda xpoint, ypoint, srch, now: [room[ypoint][xpoint].__setitem__(xpoint, "@"), srch(xpoint - 1, ypoint, srch, now) + srch(xpoint + 1, ypoint, srch, now) + srch(xpoint, ypoint + 1, srch, now) + srch(xpoint, ypoint - 1, srch, now) + 1][1] if 0 <= xpoint < wh[0] and 0 <= ypoint < wh[1] and now(xpoint, ypoint) else 0, now=lambda xpoint, ypoint: room[ypoint][xpoint].get(xpoint) is ".": [globals().__setitem__("wh", list(map(int, input().split()))), globals().__setitem__("room", []), globals().__setitem__("point", {"x": None, "y": None}), [atin(input(), ypoint) for ypoint in range(wh[1])], [room[point["y"]][point["x"]].__setitem__(point["x"], "."), print(search(point["x"], point["y"], search, now)), this(this)] if room else None])