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:
from collections import deque

while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    else:
        m = []
        d = deque()
        for i in range(h):
            r = input()
            m.append(list(r))
            s = r.find('@')
            if s != -1:
                d.append((s, i))
        while len(d):
            rw, rh = d.popleft()
            m[rh][rw] = 'Y'
            if 0 < rw and m[rh][rw-1] == '.':
                d.append((rw-1, rh))
                m[rh][rw-1] = 'Y'
            if rw < w-1 and m[rh][rw+1] == '.':
                d.append((rw+1, rh))
                m[rh][rw+1] = 'Y'
            if 0 < rh and m[rh-1][rw] == '.':
                d.append((rw, rh-1))
                m[rh-1][rw] = 'Y'
            if rh < h-1 and m[rh+1][rw] == '.':
                d.append((rw, rh+1))
                m[rh+1][rw] = 'Y'
        a = 0
        for i in m:
            a += i.count('Y')
        print(a)