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:
adjR = [-1, 0, 0, 1]
adjC = [0, 1, -1, 0]

def isValid(row, col, ROWS, COLS):
    return row >= 0 and row < ROWS and col >= 0 and col < COLS

def floodfill(board, row, col, ROWS, COLS):
    global adjR
    global adjC

    if not isValid(row, col, ROWS, COLS):
        return 0
    if board[row][col] == '#':
        return 0

    board[row][col] = '#'
    total = 1
    for x in range(4):
        rr = row + adjR[x]
        cc = col + adjC[x]
        total += floodfill(board, rr, cc, ROWS, COLS)
    return total
    

if __name__ == '__main__':
    while True:
        COLS, ROWS = list(map(int, input().split()))
        if ROWS == 0 and COLS == 0:
            break

        board = []
        for i in range(ROWS):
            line = input()
            board.append([ c for c in line ])
            if '@' in line:
                row = i
                col = line.find('@')
        
        print(  floodfill(board, row, col, ROWS, COLS)  )