hdu red and black

题目地址：http://acm.hdu.edu.cn/showproblem.php?pid=1312

DFS：

#includeint h,w;char z[21][21];int dfs(int i,int j){  if(i<0||i>h-1||j<0||j>w-1)    return 0;  if(z[i][j]!='#'){    z[i][j]='#';    return 1+dfs(i-1,j)+dfs(i+1,j)+dfs(i,j-1)+dfs(i,j+1);  }  else return 0;}main(){  int i,j;  while(scanf("%d%d",&w,&h)!=EOF){    if(w==0&&h==0)break;    scanf("%d%d",&w,&h);    for(i=0;i

BFS：

#includeint a[25][25];int x,y,sum;int dir[4][2]={1,0,0,1,-1,0,0,-1};struct node{    int x,y;}q[500];void BFS(int x0,int y0){    int head=0,tail=1;    q[1].x=x0;    q[1].y=y0;    while(head=0&&y0>=0&&y0