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 JAVA):

Solution:
import java.awt.Point;
import java.util.ArrayDeque;
import java.util.Scanner;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.stream.IntStream;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

public class Main{
	static final Scanner s=new Scanner(System.in);
	static long[] fal_rnd(int size){
		AtomicInteger l=new AtomicInteger(-1),r=new AtomicInteger(size);
		long[] res=new long[size];
		INS(size).unordered().parallel().mapToLong(Long::parseLong).forEach(v->res[ThreadLocalRandom.current().nextBoolean()?l.incrementAndGet():r.decrementAndGet()]=v);
		return res;
	}
	static IntStream REPS(int v){
		return IntStream.range(0,v);
	}
	static Stream<String> INS(long size){
		return StreamSupport.stream(Spliterators.spliterator(s,size,Spliterator.NONNULL&Spliterator.IMMUTABLE),false).limit(size);
	}
	
	static long r,c;
	public static void main(String[] __){
		while(true){
			c=s.nextInt();
			r=s.nextInt();
			if(r+c==0) return;
			char[][] f=INS(r).map(String::toCharArray).toArray(char[][]::new);
			
			
			ArrayDeque<Point> deque=new ArrayDeque<>();
			
			serachStart:
			for(int i=0;i<r;i++){
				for(int j=0;j<c;j++){
					if(f[i][j]=='@'){
						deque.add(new Point(i,j));
						f[i][j]='#';
						break serachStart;
					}
				}
			}
			int res=1;
			while(!deque.isEmpty()){
				for(int l=deque.size();l>0;l--){
					Point poll=deque.pollFirst();
					for(int d=0;d<dr.length;d++) {
						Point p=(Point)(poll.clone());
						p.translate(dr[d],dc[d]);
						if(ranged(p)&&f[p.x][p.y]=='.') {
							deque.addLast(p);
							f[p.x][p.y]='#';
							res++;
						}
					}
				}
			}
			System.out.println(res);
		}
	}
	static int[] dr={0,1,0,-1},dc={-1,0,1,0};
	static boolean ranged(Point p){
		return 0<=p.x&&p.x<r&&0<=p.y&&p.y<c;
	}
}