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:
while 1:
	w,h = map(int, raw_input().split())
	if w == h == 0:
		break
	count = 0
	cnt = 1
	lst = [list(raw_input()) for i in range(h)]
	queue = []
	for i in range(h):
		if "@" in lst[i]:
			wNow, hNow = lst[i].index("@"),i
	queue.append([hNow, wNow])
	while 1:
		hNow,wNow = queue[0][0],queue[0][1]
		queue.pop(0)
		if hNow < h-1:
			if lst[hNow+1][wNow] == ".":
				queue.append([hNow+1,wNow])
				lst[hNow+1][wNow] = "$"
				cnt += 1
		if wNow < w-1:
			if lst[hNow][wNow+1] == ".":
				queue.append([hNow,wNow+1])
				lst[hNow][wNow+1] = "$"
				cnt += 1
		if hNow > 0:
			if lst[hNow-1][wNow] == ".":
				queue.append([hNow-1,wNow])
				lst[hNow-1][wNow] = "$"
				cnt += 1
		if wNow > 0:
			if lst[hNow][wNow-1] == ".":
				queue.append([hNow,wNow-1])
				lst[hNow][wNow-1] = "$"
				cnt += 1
		if len(queue) == 0:
			break
	print cnt