迷宫-递归算法
迷宫，递归实现：
1 /* 2 迷宫之递归，能够输出所有的路线。 3 */ 4 #include <iostream> 5 #include <time.h> 6 using namespace std; 7 typedef struct Position{ 8 int x; 9 int y; 10 }POSITION,*pPOSiTION; 11 12 int MazeMapLineNumber =0; 13 pPOSiTION pMazePath; 14 int PathLength = 0; 15 bool IsOutOfBorder(int x,int y); 16 void Go(pPOSiTION pos);//将当前位置放入迷宫路线中 17 void Try(int **pMap,pPOSiTION begin,pPOSiTION end);//开始找路 18 bool Showpath(); 19 int main() { 20 int **pMap = NULL; 21 pPOSiTION begin = new POSITION; 22 pPOSiTION end = new POSITION; 23 int i=0,j=0; 24 srand((unsigned)time(NULL)); 25 cout<<"Please input the row of the maze map:"; 26 cin>>MazeMapLineNumber; 27 pMap = new int *[MazeMapLineNumber]; 28 for (i=0;i<MazeMapLineNumber;i++) { 29 pMap[i] = new int [MazeMapLineNumber]; 30 } 31 32 //动态生成一个二维数组，用于地图 33 for (i=0;i<MazeMapLineNumber;i++) { 34 for (j=0;j<MazeMapLineNumber;j++) { 35 pMap[i][j] = rand()%2; 36 cout<<pMap[i][j]<<" "; 37 } 38 cout<<"\n"; 39 } 40 cout<<endl; 41 //该for循环主要输出对应点的坐标，节省输入时间。 42 for (i=0;i<MazeMapLineNumber;i++) { 43 for (j=0;j<MazeMapLineNumber;j++) { 44 cout<<pMap[i][j]<<"("<<i<<","<<j<<")"<<" "; 45 } 46 cout<<"\n"; 47 } 48 pMazePath = new POSITION[MazeMapLineNumber*MazeMapLineNumber]; 49 cout<<"Please input start's x and y:"; 50 cin>>begin->x>>begin->y; 51 cout<<"Please input end's x and y:"; 52 cin>>end->x>>end->y; 53 Go(begin); 54 pMap[begin->x][begin->y] = 0; 55 Try(pMap,begin,end); 56 57 if(PathLength == 0) cout<<"There is no way to pass the maze"<<endl; 58 return 0; 59 } 60 61 62 63 bool IsOutOfBorder(int x,int y) { 64 if(x<0||x>=MazeMapLineNumber||y<0||y>=MazeMapLineNumber) return true; 65 else return false; 66 } 67 68 void Go(pPOSiTION pos){ 69 pMazePath[PathLength].x=pos->x; 70 pMazePath[PathLength].y=pos->y; 71 PathLength++; 72 } 73 void Try(int **pMap,pPOSiTION begin,pPOSiTION end) { 74 POSITION NextPos[4] = {{0,1},{1,0},{0,-1},{-1,0}}; 75 pPOSiTION next = new POSITION; 76 next->x = begin->x; 77 next->y = begin->y; 78 //cout<<"next1:"<<next->x<<","<<next->y<<endl; //方便调试。。下同 79 int i=0; 80 if(next->x==end->x && next->y==end->y) { 81 Showpath(); 82 } else { 83 for (i=0;i<4;i++) { 84 //cout<<"begin1:"<<begin->x<<","<<begin->y<<endl; 85 next->x =begin->x + NextPos[i].x; 86 next->y =begin->y + NextPos[i].y; 87 //cout<<"begin2:"<<begin->x<<","<<begin->y<<endl; 88 if(!IsOutOfBorder(next->x,next->y)&&pMap[next->x][next->y]==1) { 89 Go(next); 90 pMap[next->x][next->y] = 0;//将当前的点置为不可行 91 //cout<<"next2:"<<next->x<<","<<next->y<<endl; 92 Try(pMap,next,end); 93 pMap[next->x][next->y] = 1;//恢复可行，让下一次可以使用该点 94 PathLength--;//迷宫路线长度-1，代表该路线已经探索完毕。 95 } 96 } 97 } 98 99 } 100 101 bool Showpath() { 102 static int num; 103 if(PathLength == 0) { 104 cout<<"There is no way to pass the maze"<<endl; 105 return false; 106 } 107 cout<<"Path"<<num++<<":"<<endl; 108 for(int i=0;i<PathLength-1;i++) { 109 cout<<"("<<pMazePath[i].x<<","<<pMazePath[i].y<<")"<<"->"; 110 } 111 cout<<"("<<pMazePath[PathLength-1].x<<","<<pMazePath[PathLength-1].y<<")"<<endl; 112 return true; 113 }
之前用栈写了一个迷宫，但是无法输出全部路线，现在学到递归函数了，发现能够全部输出全部的路线
递归虽然占用资源，但是用起来却是很方便。一步一步踏踏实实的向前进行！加油！
顺带一个汉诺塔的小函数,同样是递归
1 /* 2 汉诺塔算法：1：将A上的n-1个盘子借助C移到B上。 3 2：将A上的第n个盘子移到C上。 4 3：将B上的n-1盘子借助A移到C上。 5 */ 6 #include <stdio.h> 7 void game(int n,char A,char B,char C);//将A上的盘子借助B移动到C 8 int main() { 9 char A = 'A',B='B',C='C'; 10 game(2,A,B,C); 11 return 0; 12 } 13 14 void game(int n,char A,char B,char C) { 15 if(1 == n) { 16 printf("Please put plate %d to %c from %c \n",n,C,A); 17 } else { 18 game(n-1,A,C,B); 19 printf("Please put plate %d to %c from %c \n",n,C,A); 20 game(n-1,B,A,C); 21 } 22 }
上述两个应该都算入门级递归算法吧。为以后学习树和图打下好的基础吧。。。加油！
