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

def solve(W, H, field):
    dire = [(1,0), (0,1), (-1,0), (0,-1)]
    for i in range(H):
        for j in range(W):
            if (field[i][j]=="@"):
                s = (i,j)
    check = [[0]*W for i in range(H)]
    q = deque()
    q.append(s)
    check[s[0]][s[1]] = 1
    ret = 1
    while q:
        y, x = q.popleft()
        for dy, dx in dire:
            if (y+dy<H) and (y+dy>=0) and (x+dx<W) and (x+dx>=0):
                if (field[y+dy][x+dx] == ".") and (not check[y+dy][x+dx]):
                    q.append((y+dy, x+dx))
                    check[y+dy][x+dx] = 1
                    ret += 1
    return ret

def main():
    ans = []
    while True:
        W, H = list(map(int, input().split()))
        if (not W) and (not H):
            break
        field = [input() for i in range(H)]
        ans.append(solve(W, H, field))
    for i in ans:
        print(i)
    
main()