迷宫问题bfs, A Knight's Journey(dfs)
作者:互联网
迷宫问题(bfs)
POJ - 39841 #include <iostream> 2 #include <queue> 3 #include <stack> 4 #include <cstring> 5 6 using namespace std; 7 8 /*广度优先搜索*/ 9 /*将每个未访问过的邻接点进队列,然后出队列,知道到达终点*/ 10 11 typedef class 12 { 13 public: 14 int x; 15 int y; 16 }coordinate; 17 18 int maze[5][5]; //迷宫 19 int road[4][2] = { { 0, -1 }, { 1, 0 }, { -1, 0 }, { 0, 1 } }; 20 coordinate pre[20][20]; //记录当前坐标的前一个坐标 21 22 int visited[5][5] = { 0 }; 23 24 /*利用一个栈,倒序输出pre中存入的坐标*/ 25 void print() 26 { 27 stack<coordinate> S; 28 coordinate rhs = { 4, 4 }; 29 30 while (1) 31 { 32 S.push(rhs); 33 if (rhs.x == 0 && rhs.y == 0) 34 break; 35 rhs = pre[rhs.x][rhs.y]; 36 } 37 38 while (!S.empty()) 39 { 40 rhs = S.top(); 41 S.pop(); 42 cout << "(" << rhs.x << ", " << rhs.y << ")" << endl; 43 } 44 } 45 46 void bfs(int x, int y) 47 { 48 queue<coordinate> Q; //用来帮助广度优先搜索 49 coordinate position; 50 51 position.x = x, position.y = y; 52 53 Q.push(position); 54 55 while (!Q.empty()) 56 { 57 position = Q.front(); 58 Q.pop(); 59 60 visited[position.x][position.y] = 1; 61 coordinate position2; 62 63 if (position.x == 4 && position.y == 4) //如果找到终点,停止搜索 64 { 65 print(); 66 return; 67 } 68 69 for (int i = 0; i < 4; i++) 70 { 71 72 position2.x = position.x + road[i][0]; 73 position2.y = position.y + road[i][1]; 74 75 if (position2.x >= 0 && position2.x <= 4 && position2.y >= 0 && position2.y <= 4 && maze[position2.x][position2.y] == 0 && !visited[position2.x][position2.y]) //如果这个邻接点不是墙且未访问过,则进队列 76 { 77 Q.push(position2); 78 pre[position2.x][position2.y] = position; //记录当前坐标的前一个坐标位置 79 visited[position2.x][position2.y] = 1; 80 } 81 82 } 83 } 84 } 85 86 int main() 87 { 88 memset(maze, 0, sizeof(pre)); 89 for (int i = 0; i < 5; i++) 90 for (int j = 0; j < 5; j++) 91 { 92 cin >> maze[i][j]; 93 } 94 95 //memset(pre, 0, sizeof(pre)); //现将pre初始化 96 97 bfs(0, 0); 98 99 100 return 0; 101 }
A Knight's Journey
OpenJ_Bailian - 24881 #include <cstring> 2 #include<iostream> 3 using namespace std; 4 5 char route[27][2]; //记录行驶的路线 6 int board[9][9]; //棋盘 7 8 int total = 0; 9 int length; 10 /*dfs深度优先搜索*/ 11 12 int go[8][2] = { { -1, -2 }, { 1, -2 }, { -2, -1 }, { 2, -1 }, { -2, 1 }, { 2, 1 }, { -1, 2 }, { 1, 2 } };//字典序方向 13 14 /*一次跳跃*/ 15 void knight(int p, int q,int len ,int row, int col) //len为行走的距离,用来判断是否遍历整个棋盘, row和col为当前坐标 16 { 17 board[row][col] = 1; 18 route[len][0] = col + 'A' - 1, route[len][1] = row + '0'; 19 length = len; 20 /*让马分别尝试8个方向的跳跃,知道跳不动为止*/ 21 22 int x, y; 23 24 for (int i = 0; i < 8; i++) 25 { 26 27 x = row + go[i][0]; 28 y = col + go[i][1]; 29 30 if (x >0 && x <= p && y > 0 && y <= q && board[x][y] == 0) 31 knight(p, q, len + 1, x, y); 32 } 33 34 /*if (row - 1 >= 1 && col - 2 > 0 && board[row - 1][col - 2] == 0) 35 knight(p, q, len + 1, row - 1, col - 2); 36 37 if (row + 1 <= p && col - 2 > 0 && board[row + 1][col - 2] == 0) 38 knight(p, q, len + 1, row + 1, col - 2); 39 40 if (row - 2 >= 1 && col - 1 > 0 && board[row - 2][col - 1] == 0) 41 knight(p, q, len + 1, row - 2, col - 1); 42 43 if (row + 2 <= p && col - 1 > 0 && board[row + 2][col - 1] == 0) 44 knight(p, q, len + 1, row + 2, col - 1); 45 46 if (row - 2 >= 1 && col + 1 <= q && board[row - 2][col + 1] == 0) 47 knight(p, q, len + 1, row - 2, col + 1); 48 49 if (row + 2 <= p && col + 1 <= q && board[row + 2][col + 1] == 0) 50 knight(p, q, len + 1, row + 2, col + 1); 51 52 if (row - 1 >= 1 && col + 2 <= q && board[row - 1][col + 2] == 0) 53 knight(p, q, len + 1, row - 1, col + 2); 54 55 if (row + 1 <= p && col + 2 <= q && board[row + 1][col + 2] == 0) 56 knight(p, q, len + 1, row + 1, col + 2);*/ 57 58 } 59 60 int main() 61 { 62 int N, p, q; //行数, 每次的宽和高 63 cin >> N; 64 65 while (N--) 66 { 67 cin >> p >> q; 68 knight(p, q, 0, 1, 1); //以行走了0个单元 69 cout << "Scenario #" << ++total << ":" << endl; 70 if (length == p * q - 1) 71 { 72 73 for (int i = 0; i <= length; i++) 74 cout << route[i][0] << route[i][1]; 75 cout << endl << endl; 76 } 77 else 78 cout << "impossible" << endl << endl; 79 memset(board, 0, sizeof(board)); //清空棋盘的足迹 80 memset(route, 0, sizeof(route)); //清空路线 81 } 82 83 return 0; 84 }
标签:int,Knight,dfs,bfs,len,&&,position,col,row 来源: https://blog.51cto.com/u_14201949/2832078