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:
W,H=(int(i) for i in input().split())
while W!=0 or H!=0:
    a=[]
    T=[]
    for i in range(H):
        T.append(input())
        a.append([])
        for j in range(W):
            a[i].append(0)
 #   print(T[0][0])
    i=0
    j=0
    while T[i][j]!="@":
        j=0
        while j<W and T[i][j]!="@":
            j+=1
    #        print(j)
        if j>=W:
            j-=1
        if T[i][j]!="@":
            i+=1
  #      print(i)
    s=[[i,j]]
    a[i][j]=1
    c=1
    while s!=[]:
        u=[]
        for l in range(len(s)):
            i=s[l][0]
            j=s[l][1]
            i-=1
            k=0
            while k<2:
            #    print(j)
                if 0<=i<H and a[i][j]==0 and T[i][j]==".":
                    a[i][j]=1
                    u.append([i,j])
                    c+=1
                i+=2
                k+=1
            i-=3
            j-=1
            k=0
            while k<2:
                if 0<=j<W and a[i][j]==0 and T[i][j]==".":
                    a[i][j]=1 
                    u.append([i,j])
                    c+=1
                j+=2
                k+=1
        s=u
    #    print (a)
    print(c)
    W,H=(int(i) for i in input().split())