codevs——T2806 红与黑

 1 #include <cstring>
 2 #include <cstdio>
 3 
 4 using namespace std;
 5 
 6 int m,n,if_break;
 7 char map[25][25];
 8 
 9 int fx[4]={0,1,-1,0};
10 int fy[4]={1,0,0,-1};
11 int ans;
12 void DFS(int x,int y)
13 {    
14     for(int i=0;i<4;i++)
15     {
16         int tox=x+fx[i],toy=y+fy[i];
17         if(map[tox][toy]==‘#‘||map[tox][toy]==‘@‘) continue;
18         if(tox<0||toy<0||tox>=n||toy>=m) continue;
19         ans++;map[tox][toy]=‘#‘;
20         DFS(tox,toy);        
21     }
22 }
23 
24 int main()
25 {
26     while(scanf("%d%d",&m,&n)&&n&&m)
27     {
28         for(int i=0;i<n;i++)
29             scanf("%s",map[i]);
30         for(int i=0;i<n;i++)
31             for(int j=0;j<m;j++)
32              {
33                   if(map[i][j]==‘@‘)
34                 {    
35                     DFS(i,j);
36                     printf("%d\n",ans+1);
37                     if_break=1; break;
38                 }
39                 if(if_break) break;
40               }
41         ans=if_break=0;                        
42     }
43     return 0;
44 }

 1 #include <cstring>
 2 #include <cstdio>
 3 #include <queue>
 4 
 5 using namespace std;
 6 
 7 int m,n,if_break;
 8 char map[25][25];
 9 
10 int fx[4]={0,1,-1,0};
11 int fy[4]={1,0,0,-1};
12 int inq[2333][2333];
13 queue<int>qx;
14 queue<int>qy;
15 int BFS(int x,int y)
16 {
17     int tox,toy,ret=1;
18     qx.push(x);qy.push(y);
19     inq[x][y]=1;
20     while(!qx.empty()&&!qy.empty())
21     {
22         x=qx.front();qx.pop();
23         y=qy.front();qy.pop();
24         for(int i=0;i<4;i++)
25         {
26             tox=fx[i]+x;toy=y+fy[i];
27             if(map[tox][toy]==‘#‘||inq[tox][toy]) continue;
28             if(tox<0||toy<0||tox>=n||toy>=m) continue;
29             ret++; inq[tox][toy]=1;
30             qx.push(tox);qy.push(toy);
31         }
32     }
33     return ret;
34 }
35 
36 int main()
37 {
38     while(scanf("%d%d",&m,&n)&&n&&m)
39     {
40         memset(inq,0,sizeof(inq));
41         for(int i=0;i<n;i++)
42             scanf("%s",map[i]);
43         for(int i=0;i<n;i++)
44             for(int j=0;j<m;j++)
45              {
46                   if(map[i][j]==‘@‘)
47                 {    
48                     printf("%d\n",BFS(i,j));
49                     if_break=1; break;
50                 }
51                 if(if_break) break;
52               }
53         if_break=0;                
54     }
55     return 0;
56 }