HDU 1242 Rescue 营救天使

  1 #include<cstdio>
  2 #include<string.h>
  3 #include<queue>
  4 using namespace std;
  5 int m,n,i,j,ans,map[205][205],ex,ey,bx,by;
  6 int dx[4]={-1,1,0,0};
  7 int dy[4]={0,0,-1,1};
  8 char str[205];
  9 struct stu
 10 {
 11     int x,y,step;
 12     bool friend operator <(stu a,stu b)
 13     {
 14         return a.step>b.step;
 15     }
 16 }st;
 17 int bfs()
 18 {
 19     priority_queue<stu>que;
 20     int x,y,i,time;
 21     stu next;
 22     
 23     st.x=bx;
 24     st.y=by;
 25     st.step=0;
 26     que.push(st);
 27     while(!que.empty())
 28     {
 29         
 30         st=que.top();
 31         que.pop();
 32         time=st.step;
 33         x=st.x;
 34         y=st.y;
 35         for(i=0;i<4;i++)
 36         {
 37             st.x=x+dx[i];
 38             st.y=y+dy[i];
 39             if(st.x>=0 &&st.y>=0&&st.x<m&&st.y<m&&map[st.x][st.y]!=0)
 40             {
 41                 if(st.x == ex && st.y == ey)
 42                 {
 43                     return time+1;
 44                 }
 45                 if(map[st.x][st.y] == 2)
 46                 {
 47                     st.step=time+2;
 48                 }
 49                 else 
 50                 {
 51                     st.step=time+1;
 52                 }
 53                 map[st.x][st.y]=0;
 54                 que.push(st);
 55             }
 56         }
 57     }
 58     return 0;
 59 }
 60 int main()
 61 {
 62     while(scanf("%d %d",&m,&n)!=EOF)
 63     {
 64         memset(map,0,sizeof(map));
 65         for(i = 0 ; i < m ; i++)
 66         {
 67             scanf("%s",&str);
 68             for(j = 0 ;j < n ; j++)
 69             {
 70                 if(str[j] == ‘.‘)
 71                 {
 72                     map[i][j]=1;
 73                 }
 74                 if(str[j] == ‘x‘)
 75                 {
 76                     map[i][j]=2;
 77                 }
 78                 if(str[j] == ‘a‘)
 79                 {
 80                     map[i][j]=1;
 81                     ex=i;
 82                     ey=j;
 83                 }
 84                 if(str[j] == ‘r‘)
 85                 {
 86                     map[i][j]=1;
 87                     bx=i;
 88                     by=j;
 89                 }
 90             }
 91         }    
 92     /*    for( i = 0 ; i < m ; i++)
 93          {
 94             for(j =0 ; j < n ; j++)
 95              {
 96                 printf("%d  ",map[i][j]);
 97                  if(j == n-1)
 98                  {
 99                      printf("\n");
100                  }
101             }
102          }            */
103         map[bx][by]=0;
104         ans=bfs();
105         if(ans)
106             printf("%d\n",ans);
107         else
108             printf("Poor ANGEL has to stay in the prison all his life.\n");
109         
110     }
111 }