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:
import sys
sys.setrecursionlimit(10000000)
MOD = 10 ** 9 + 7
INF = 10 ** 15
Dy = (-1,0,1,0)
Dx = (0,1,0,-1)

from collections import deque,defaultdict,Counter
def solve(H,W):
    grid = [input() for _ in range(H)]
    cnt = [[0]*W for _ in range(H)]
    for i in range(H):
        for j in range(W):
            if grid[i][j] == '@':
                sy,sx = i,j
                break
    
    q = deque([(sy,sx)])
    cnt[sy][sx] = 1
    ans = 1
    while q:
        ny,nx = q.popleft()
        for dy,dx in zip(Dy,Dx):
            y = ny + dy
            x = nx + dx
            if y < 0 or y >= H:
                continue
            if x < 0 or x >= W:
                continue
            if grid[y][x] == '#':
                continue
            if cnt[y][x] == 1:
                continue
            cnt[y][x] = 1
            ans += 1
            q.append((y,x))
    print(ans)
    
def main():
    while True:
        W,H = map(int,input().split())
        if H == 0 and W == 0:
            return
        solve(H,W)
if __name__ == '__main__':
    main()