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:
# coding: utf-8

import sys

def dfs(rw,cm):
    global flag
    flag[rw][cm] = 1
    if 0 <= rw - 1 and mp[rw-1][cm] == '.' and flag[rw-1][cm] == 0:
        dfs(rw-1,cm)
    if cm + 1 < m and mp[rw][cm+1] == '.' and flag[rw][cm+1] == 0:
        dfs(rw,cm+1)
    if 0 <= cm - 1 and mp[rw][cm-1] == '.' and flag[rw][cm-1] == 0:
        dfs(rw,cm-1)
    if rw + 1 < n and mp[rw+1][cm] == '.' and flag[rw+1][cm] == 0:
        dfs(rw+1,cm)

if __name__ == '__main__':
    while 1:
        m,n = map(int,input().split())
        if m == 0 and n == 0:
            break
        mp = []
        for i in range(n):
            mp.append(list(input()))
            if '@' in mp[-1]:
                stj = mp[-1].index('@')
                sti = i
        flag = [[0 for i in range(m)] for j in range(n)]
        dfs(sti,stj)
        print(sum(flag[i].count(1) for i in range(n)))