Problem 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)
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
45
59
6
13
#includeusing namespace std;char mapp[65][65];int m,n,k=0,c=0,d=0;void dfs(int x,int y){ if(mapp[x][y]=='#'||x<0||y<0||x>=m||y>=n) { return; } mapp[x][y]='#'; dfs(x+1,y); dfs(x-1,y); dfs(x,y+1); dfs(x,y-1);}int main(){ int i,j,k; while(cin>>n>>m) { c=0; d=0; if(m==0&&n==0) break; for(i=0;i >mapp[i][j]; } } for(i=0;i