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:
import sys

ct=1
def count(Map, w,h,i, j):
    global ct
    dx=[1,0,-1,0]
    dy=[0,1,0,-1]
    for k in range(4):
        ix=i+dy[k]
        jx=j+dx[k]
        if (0<=ix<h and 0<=jx<w and Map[ix][jx]=='.'):
            Map[ix][jx]='#'
            ct+=1
            count(Map,w,h,ix,jx)

while(True):
    input = map(int, sys.stdin.readline().replace('\n','').split(' '))
    w,h=input
    if(w==0 and h==0):break
    Map=[]
    for i in range(h):
        s=raw_input()
        Map.append(list(s))
        
    flag=False
    for i in range(h):
        for j in range(w):
            if (Map[i][j]=='@'):
                flag=True
                Map[i][j]='#'
                break
        if flag:break

    ct=1
    count(Map,w,h,i,j)
    print ct