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 queue import *


d = [(1,0),(0,1),(-1,0),(0,-1)]
temp={}

while True:
    W,H = (int(x) for x in input().split())
    mmap=[]
    visited=[]
    flag=0
    count=1
    
    q = Queue()
    
    if W==0 & H==0:
        break
    for i in range(0,H):
        mmap.append(list(input()))
    for i in range (0,H):
        for j in range(0,W):
            if mmap[i][j] == '@':
                start=[i,j]
    
    q.put(start)
    visited.append(list(start))
    while not q.empty():
        now = q.get()
        for myd in d:
            now2 = list(now)
            now2[0] += myd[0]
            now2[1] += myd[1]
            if not(now2[0]==-1 or now2[0]==H or now2[1]==-1 or now2[1]==W) :
                if mmap[now2[0]][now2[1]] != '#' :
                    flag=0
                    for v in visited:
                        if now2 == v :
                            flag=1
                            break
                    if flag==0:
                        count+=1
                        q.put(now2)
                        visited.append(list(now2))
    
    print(count)