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 collections import deque

ans = []
while True:
    w, h = map(int, input().split())
    if not w and not h:
        break
    
    roadmap = []
    d = deque()
    able = [[False for i in range(w)] for j in range(h)]
    for i in range(h):
        roadmap.append(input())
        
    
    for i in range(h):
        for j in range(w):
            if roadmap[i][j] == '@':
                able[i][j] = True
                d.append([i, j])

    
    while len(d):
        y, x = d.pop()
        
        for course in [[0, 1], [1, 0], [-1, 0], [0, -1]]:
            tmpy, tmpx = y + course[0], x + course[1]
            if tmpy < 0 or tmpy >= h or tmpx < 0 or tmpx >= w:
                continue
                
            if not able[tmpy][tmpx] and roadmap[tmpy][tmpx] == '.':
                able[tmpy][tmpx] = True
                d.append([tmpy, tmpx])

    a = 0
    for i in range(h):
        a += len(list(filter(lambda x:x, able[i])))

    ans.append(a)

[print(i) for i in ans]