数据结构学习之回溯法求解迷宫问题

#include 
#include 
using namespace std;

// 把迷宫表示为n个有编码路口的集合
// 定义路口类
class Crossing
{
public:
	// 0为不通 路口的三个方向
	int turn1;
	int turn2;
	int turn3;

public:
	Crossing(int turn1, int turn2, int turn3)
	{
		Crossing::turn1 = turn1;
		Crossing::turn2 = turn2;
		Crossing::turn3 = turn3;
	}	
};

// 定义迷宫类
class Maze
{
private:
	int exit; //出口编码
	vector crossings; //路口集合
	vector result;

public:
	Maze(int the_exit, vector the_crossings)
	{
		exit = the_exit;
		crossings = the_crossings;
	}
	findExit(int entrance); //迷宫求解
	getResult(); //取得迷宫解并打印
	
};

//迷宫求解核心算法
Maze::findExit(int entrance)
{
	if(entrance > 0)
	{
		if(entrance == Maze::exit)
		{
			result.push_back(entrance);
			return 1;
		}
		if(findExit(crossings[entrance].turn1))
		{
			result.push_back(entrance);
			return 1;
		}
		if(findExit(crossings[entrance].turn2))
		{
			result.push_back(entrance);
			return 1;
		}
		if(findExit(crossings[entrance].turn3))
		{
			result.push_back(entrance);
			return 1;
		}
	}

	return 0;
}

Maze::getResult()
{
	findExit(1);
	
	for(int i = result.size(); i>0; i--)
		cout << result[i-1] << "->";
	cout << "Exit" << endl;
}

void main()
{
	// 创建一个迷宫 9个路口 出口为10
	Crossing c1(2,0,0);
	Crossing c2(4,0,0);
	Crossing c3(0,0,0);
	Crossing c4(3,5,0);
	Crossing c5(6,0,0);
	Crossing c6(7,0,0);
	Crossing c7(8,9,0);
	Crossing c8(0,0,0);
	Crossing c9(10,0,0);
	Crossing c0(0,0,0);

	vector crossings;
	crossings.push_back(c0);
	crossings.push_back(c1);
	crossings.push_back(c2);
	crossings.push_back(c3);
	crossings.push_back(c4);
	crossings.push_back(c5);
	crossings.push_back(c6);
	crossings.push_back(c7);
	crossings.push_back(c8);
	crossings.push_back(c9);

	Maze newMaze(10, crossings);
	newMaze.getResult();

	return;
}