（图 BFS）走迷宫

  1 #include <iostream>
  2 #include <queue>
  3 #include <fstream>
  4 #include <string>
  5 #include <iomanip>
  6 
  7 using std::cout;
  8 using std::endl;
  9 using std::cin;
 10 using std::string;
 11 
 12 class Maze
 13 {
 14 public:
 15     Maze(string file);
 16     ~Maze();
 17     void showMaze(void) const;
 18     void getPath(void);
 19     void calc(void);
 20     void showPreNode(void) const;
 21     void showPath(void) const;
 22 
 23 private:
 24     int m_rows;
 25     int m_colomns;
 26     bool** m_pData;        //用bool装迷宫数据
 27 
 28     int** m_preNode;        //记录路径，也就是前一个节点
 29     bool** m_flag;        //标志是否访问过
 30     enum { INVALID = -1 };
 31     
 32     struct Coord        //定义一个坐标
 33     {
 34         int x;
 35         int y;
 36 
 37         bool operator ==(const Coord& rhs)
 38         {
 39             if (this->x == rhs.x && this->y == rhs.y)
 40                 return true;
 41             return false;
 42         }
 43     };
 44 
 45     void initeAboutCalc(void);
 46     Coord getAssignCoord(const Coord& thisCoord, int num) const;
 47     void showPathPre(int x, int y) const;
 48 };
 49 
 50 Maze::Maze(string file)
 51 {
 52     std::ifstream fin(file);
 53     fin >> m_rows >> m_colomns;
 54 
 55     //分配数据区
 56     m_pData = new bool*[m_rows];
 57     for (int i = 0; i < m_rows; i++)
 58         m_pData[i] = new bool[m_colomns];
 59 
 60     //读取数据
 61     for (int i = 0; i < m_rows; i++)
 62     {
 63         for (int j = 0; j < m_colomns; j++)
 64             fin >> m_pData[i][j];
 65     }
 66 
 67     //初始化其他
 68     initeAboutCalc();
 69 }
 70 
 71 void Maze::initeAboutCalc(void)
 72 {
 73     m_preNode = new int*[m_rows];
 74     m_flag = new bool*[m_rows];
 75     
 76     for (int i = 0; i < m_rows; i++)
 77     {
 78         m_preNode[i] = new int[m_colomns];
 79         memset(m_preNode[i], INVALID, m_colomns * sizeof(int));
 80 
 81         m_flag[i] = new bool[m_colomns];
 82         memset(m_flag[i], false, m_colomns * sizeof(bool));
 83     }
 84 }
 85 
 86 Maze::~Maze()
 87 {
 88     for (int i = 0; i < m_rows; i++)
 89         delete[] m_pData[i];
 90 
 91     delete[] m_pData;
 92 }
 93 
 94 void Maze::showMaze(void) const
 95 {
 96     for (int i = 0; i < m_rows; i++)
 97     {
 98         for (int j = 0; j < m_colomns; j++)
 99             cout << m_pData[i][j] << " ";
100 
101         cout << endl;
102     }
103 }
104 
105 void Maze::calc(void)
106 {
107     const Coord START = { 0, 0 };
108     const Coord END = { m_rows - 1, m_colomns - 1 };
109     const Coord ERROR_COORD = { -1, -1 };
110 
111     std::queue<Coord> que;        //二维数组下标放到队列里面去
112     m_flag[START.x][START.y] = true;
113     que.push(START);        //起点
114 
115     while (true)
116     {
117         Coord thisNode = que.front();
118         que.pop();
119         if (thisNode == END)
120             break;
121 
122         //对于这一点的上下左右个点
123         for (int i = 0; i < 8; i++)
124         {
125             Coord coordTemp = getAssignCoord(thisNode, i);
126             if (coordTemp == ERROR_COORD || 0 == m_pData[coordTemp.x][coordTemp.y])        //没有这点或者这点是墙
127                 continue;
128 
129             if (!m_flag[coordTemp.x][coordTemp.y])        //没有访问过
130             {
131                 m_flag[coordTemp.x][coordTemp.y] = true;
132                 m_preNode[coordTemp.x][coordTemp.y] = thisNode.x * m_colomns + thisNode.y;        //注意这里用的不是坐标了，但也可唯一确定一个点
133                 que.push(coordTemp);
134             }
135         }
136     }
137 }
138 
139 Maze::Coord Maze::getAssignCoord(const Coord& thisCoord, int num) const
140 {
141     Coord res = { -1, -1 };        //不合法的
142     if (num < 0 || num >= 4)
143         return res;
144 
145     switch (num)
146     {
147     case 0:
148         {
149               if (!thisCoord.x)
150                   return res;
151               res.x = thisCoord.x - 1;
152               res.y = thisCoord.y;
153         }
154     case 1:
155         {
156               if (thisCoord.y == m_colomns - 1)
157                   return res;
158               res.x = thisCoord.x;
159               res.y = thisCoord.y +1;
160         }
161     case 2:
162         {
163               if (thisCoord.x == m_rows - 1)
164                   return res;
165               res.x = thisCoord.x + 1;
166               res.y = thisCoord.y;
167         }
168     case 3:
169         {
170               if (!thisCoord.y)
171                   return res;
172               res.x = thisCoord.x;
173               res.y = thisCoord.y - 1;
174         }
175     }
176     return res;
177 }
178 
179 void Maze::showPreNode(void) const
180 {
181     for (int i = 0; i < m_rows; i++)
182     {
183         for (int j = 0; j < m_colomns; j++)
184             cout << std::setw(3) << std::left << m_preNode[i][j];
185 
186         cout << endl;
187     }
188 }
189 
190 void Maze::showPath(void) const
191 {
192     showPathPre(m_rows - 1, m_colomns - 1);
193 }
194 
195 void Maze::showPathPre(int x, int y) const
196 {
197     if (0 == x && 0 == y)
198     {
199         cout << "(" << x << ", " << y << ")" << endl;
200     }
201     else
202     {
203         showPathPre(m_preNode[x][y] / m_colomns, m_preNode[x][y] % m_colomns);
204         cout << " -> (" << x << ", " << y << ")" << endl;
205     }
206 }
207 
208 int main(void)
209 {
210     Maze maze("src.txt");
211     maze.showMaze();
212     cout << endl;
213     maze.calc();
214     maze.showPreNode();
215     cout << endl;
216     maze.showPath();
217     cin.get();
218 }