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:
#! /usr/bin/env python
# -*- coding: utf-8 -*-

def rec(x, y, used, TILE):
    if not(0<=x<W) or not(0<=y<H):
        return
    elif used[y][x]==1 or TILE[y][x]=='#':
        return
    else:
        used[y][x] = 1
        rec(x-1, y, used, TILE)
        rec(x+1, y, used, TILE)
        rec(x, y-1, used, TILE)
        rec(x, y+1, used, TILE)

(W, H) = map(int, raw_input().split())
while W!=0:
    used = [[0]*W for i in range(H)]
    TILE = []
    s = []
    for i in range(H):
        TILE.append(raw_input())
    for i in range(H):
        for j in range(W):
            if TILE[i][j] == '@':
                s = [i, j]

    #print s[0], s[1]
    #print used
    #print TILE
    rec(s[1], s[0], used, TILE)
    Sum = 0
    for i in range(H):
        Sum += used[i].count(1)
    print Sum
    #print used.count(1)

    (W, H) = map(int, raw_input().split())