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:
#!/usr/bin/env python3
#AOJ B
from collections import deque

def bfs():
    while 1:
        W,H = map(int,input().split())
        if W == 0 and H == 0:
            break
        maze = [list(input()) for _ in range(H)]
        check = [[False for _ in range(W)] for _ in range(H)]
        #print(maze)
        dx = [1,0,-1,0]
        dy = [0,1,0,-1]
        for i in range(H):
            for j in range(W):
                if maze[i][j] == '@':
                    sx,sy = j,i
                    check[i][j] = True

        ans = 1
        que = deque()
        que.append((sx,sy))
        while que:
            x,y = que.pop()
            for i in range(4):
                nx,ny = x + dx[i],y + dy[i]

                if 0 <= nx < W and 0 <= ny < H and maze[ny][nx] == '.' and check[ny][nx] == False:
                    que.append((nx,ny))
                    check[ny][nx] = True
                    ans += 1
        print(ans)
    return

if __name__ == '__main__':
    bfs()