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Red and Black

Time Limit: 1000MS		Memory Limit: 30000K
Total Submissions: 12004		Accepted: 6097

Description

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).

Sample Input

6 9....#......#..............................#@...#.#..#.11 9.#..........#.#######..#.#.....#..#.#.###.#..#.#..@#.#..#.#####.#..#.......#..#########............11 6..#..#..#....#..#..#....#..#..###..#..#..#@...#..#..#....#..#..#..7 7..#.#....#.#..###.###...@...###.###..#.#....#.#..0 0

Sample Output

4559613

#include
     
       using namespace std; char map[22][22]; int sum,l,h; int dir[4][2]={
    {
    1,0},{
    -1,0},{
    0,1},{
    0,-1}}; bool border(int x,int y) {
    if(x<0||x>=h||y<0||y>=l) return 0; return 1; } void search(int x,int y) {
    int i; int xx,yy;     sum++;     map[x][y]='#'; for(i=0;i<4;i++)     {
            xx=x+dir[i][0];         yy=y+dir[i][1]; if(border(xx,yy)&&map[xx][yy]=='.')         search(xx,yy);     } } int main() {
    int i,j; int x0,y0; while(cin>>l>>h)     {
            sum=0; if(l==0&&h==0)break; for(i=0;i
      
       >map[i][j]; if(map[i][j]=='@')                 {
                        x0=i;                     y0=j;                 }             }         }         search(x0,y0);         cout<
       
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