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 PYTHON):

Solution:
def walk(x, y):
        #print x,y
        global s
        global c
        global v
        if 0 <= x < w and 0 <= y < h:
                if v[y][x] is False:
                        if s[y][x] == '@' or s[y][x] == '.':
                                v[y][x] = True
                                c += 1
                                #print 'hai'
                                walk(x-1, y)
                                walk(x, y-1)
                                walk(x+1, y)
                                walk(x, y+1)

while 1:
        c = 0
        w,h = map(int, raw_input().split())
        if w == 0 and h == 0: break
        s = ['' for i in xrange(h)]
        v = [[False for j in xrange(w)] for i in xrange(h)]
        for i in xrange(h):
                s[i] = raw_input()
        for i in xrange(w):
                for j in xrange(h):
                        if s[j][i] == '@':
                                walk(i, j)
        #print v
        print c