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.
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)
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
1 #include<cstdio> 2 #include<string.h> 3 int px[4]={-1,1,0,0}; 4 int py[4]={0,0,-1,1}; 5 int ans; 6 bool key[300][300]; 7 char a[300][300]; 8 int n,m,x,y; 9 void f(int x,int y) 10 { 11 int nx,ny; 12 for(int i = 0 ;i < 4 ; i++) 13 { 14 nx=x+px[i]; 15 ny=y+py[i]; 16 if(nx >= 0 && ny >= 0 && a[nx][ny] == '.' && key[nx][ny] == false && nx < m && ny < n) 17 { 18 ans++; 19 key[nx][ny]=true; 20 f(nx,ny); 21 } 22 } 23 } 24 int main() 25 { 26 27 while(scanf("%d %d",&n,&m) && n && m) 28 { 29 memset(key,false,sizeof(key)); 30 for(int i = 0 ; i < m ; i++) 31 { 32 getchar(); 33 for(int j = 0 ; j < n ; j++) 34 { 35 scanf("%c",&a[i][j]); 36 if(a[i][j] == '@') 37 { 38 x=i; 39 y=j; 40 } 41 } 42 43 } 44 key[x][y]=true; 45 ans=0; 46 f(x,y); 47 printf("%d ",ans+1); 48 } 49 }