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:


def search(a,b,dx,dy,t,check,li,answer):
    for i in range(len(dx)):
            temp = [t[0]+dx[i],t[1]+dy[i]]
            if mapCheck(a,b,temp):
                if check[temp[1]][temp[0]] == 0:
                    if li[temp[1]][temp[0]] == '.':
                        answer += 1
                        check[temp[1]][temp[0]] = 1
                        answer = search(a,b,dx,dy,temp,check,li,answer)
    return answer
                    
                
            
def mapCheck(a,b,t):
    if t[0] <= a-1 and t[0] >=0:
        if t[1] <= b-1 and t[1] >= 0:
            return True
    return False

while True:
    li = []
    answer = 1
    start = [0,0]
    a,b = map(int, input().strip().split(' '))
    dx = [1,0,-1,0]
    dy = [0,1,0,-1]
    if a == 0 and b == 0:
        break
    for i in range(b):
        li.append(input().strip().split())
    check = [[0 for i in range(a)] for j in range(b)]
    for i in range(len(li)):
        li[i] = str(li[i])
        li[i] = list(li[i])
        del li[i][0]
        del li[i][0]
        del li[i][len(li[i])-1]
        del li[i][len(li[i])-1]
        for j in range(len(li[i])):
            if li[i][j] == '@':
                start = [j,i]
    print(search(a,b,dx,dy,start,check,li,answer))