HDOJ1035

1. /*
2. *这是杭电OJ上的一道简单题
3. *C++实现
4. *第一次尝试用面向对象的思想去做题,感觉很不错
5. */
6. #include <iostream>
7. using namespace std;
9. class Node
10. {
11. public:
12.     Node()//construction
13.     {
14.         time=0;
15.         flag=false;
16.     }
17.     void SetAction(char a)
18.     {
19.         action=a;
20.     }
21.     char GetAction()
22.     {
23.         return action;
24.     }
25.     void SetTime(int t)
26.     {
27.         time=t;
28.     }
29.     int GetTime()
30.     {
31.         return time;
32.     }
33.     void SetFlag(bool f)
34.     {
35.         flag=f;
36.     }
37.     int GetFlag()
38.     {
39.         return flag;
40.     }   
41. private:
42.     char action;
43.     int time;
44.     bool flag;
45. };
47. int main()
48. {
49.     int i,j;
50.     int row,col,sCol,curRow,curCol,nextRow,nextCol;
51.     int exitTime,loopStartT,loopTime;
52.     char action;    
53.     int flag;
54.     enum{exit=1,notExit=2};
56.     while(cin>>row>>col)
57.     {
58.         if(row==0 && col==0)
59.             break;
60.         cin>>sCol;
62.         Node nodes[10][10];
63.         for(i=0;i<row;i++)
64.         {
65.             for(j=0;j<col;j++)
66.             {
67.                 cin>>action;
68.                 nodes[i][j].SetAction(action);
69.             }
70.         }
71.         exitTime=-1;
72.         curRow=0;
73.         curCol=sCol-1;
74.         nodes[curRow][curCol].SetTime(0);
75.         nodes[curRow][curCol].SetFlag(true);    
76.         flag=0;
77.         while(1)
78.         {                   
79.             switch(nodes[curRow][curCol].GetAction())
80.             {
81.             case 'N':
82.                 nextRow=curRow-1;
83.                 nextCol=curCol;
84.                 break;
85.             case 'W':
86.                 nextRow=curRow;
87.                 nextCol=curCol-1;
88.                 break;
89.             case 'S':
90.                 nextRow=curRow+1;
91.                 nextCol=curCol;
92.                 break;
93.             case 'E':
94.                 nextRow=curRow;
95.                 nextCol=curCol+1;
96.                 break;
97.             }
98.             
99.             if(nextRow<0 || nextRow>=row || nextCol<0 || nextCol>=col)//out of grid
100.             {
101.                 exitTime=nodes[curRow][curCol].GetTime()+1;
102.                 flag=exit;
103.                 break;
104.             }
105.             if(nodes[nextRow][nextCol].GetFlag())//loop
106.             {
107.                 loopStartT=nodes[nextRow][nextCol].GetTime();
108.                 loopTime=nodes[curRow][curCol].GetTime()-loopStartT+1;
109.                 flag=notExit;
110.                 break;
111.             }
112.             nodes[nextRow][nextCol].SetTime(nodes[curRow][curCol].GetTime()+1);
113.             nodes[curRow][curCol].SetFlag(true);
114.             curRow=nextRow;
115.             curCol=nextCol;
116.         }
117.         if(flag==exit)
118.             cout<<exitTime<<" step(s) to exit"<<endl;
119.         if(flag==notExit)
120.             cout<<loopStartT<<" step(s) before a loop of "<<loopTime<<" step(s)"<<endl;
121.     }
122.     return 0;
123. }