走迷宫

通过栈将每次可以通过的路径保存起来。
但是要注意关于入口点和出口点的一些边界问题
一不小心就可能因为边界问题陷入死循环或者程序直接崩溃。

#pragma warning (disable:4996)
#include<iostream>
#include<stdlib.h>
#include<fstream>  
#include<assert.h>
#include<stack>
using namespace std;
class Pos
{
public:
    Pos(int x = 0, int y = 0)
        :_Row(x)
        , _Col(y)
    {

    }

    int _Row;
    int _Col;
};
class  Maze
{
public:
    Maze(int x = 0, int y = 0)
        :_row(x)
        , _col(y)
        , _map(NULL)
        , _start(0, 0)
    {

    }
    ~Maze()
    {
        if (_map != NULL)
        {
            for (int i = 0; i < _row; i++)
            {
                delete[] _map[i];
            }
            delete[]  _map;

        }
    }
    void SetMap();
    void ShowMap();
    bool PassMaze();
    bool IsPass(Pos s);
    int _row;
    int _col;
    int **_map;
    Pos  _start;
    int size;
};
void Maze::SetMap()
{
    char c;
    FILE *fp = fopen("maze.txt", "r");      //打开文件读取地图  
    assert(fp);
    //读取行  
    while ((c = fgetc(fp)) != ' '&&c != '\n')
    {
        _row = _row * 10 + (c - '0');
    }
    //读取迷宫列  
    while ((c = fgetc(fp)) != ' '&&c != '\n')
    {
        _col = _col * 10 + (c - '0');
    }
    //读取迷宫入口横坐标  
    while ((c = getc(fp)) != ' '&&c != '\n')
    {
        _start._Row = _start._Row * 10 + (c - '0');
    }
    //读取迷宫入口纵坐标  
    while ((c = getc(fp)) != ' '&&c != '\n')
    {
        _start._Col = _start._Col * 10 + (c - '0');
    }
    //开辟迷宫数组  
    _map = new int*[_row];
    for (int i = 0; i < _row; i++)
    {
        _map[i] = new int[_col];
    }
    for (int i = 0; i < _row; i++)
    {
        for (int j = 0; j < _col;)
        {
            c = getc(fp);  //开始按字符读取存入到_map的二维数组中
            if (c == '1' || c == '0')
            {
                _map[i][j] = c - '0';
                j++;
            }
        }
    }
    fclose(fp);     //关闭文件  
}
void Maze::ShowMap()
{
    for (int i = 0; i < _row; i++)
    {
        for (int j = 0; j < _col; j++)
        {
            printf("%d ", _map[i][j]);
        }
        cout << endl;
    }
}
bool Maze::IsPass(Pos s)
{
    if (s._Row>=0&&s._Row<_row&&s._Col>=0&&s._Col<_col&&_map[s._Row][s._Col] == 0)
    {
        return true;
    }
    else if (s._Row < 0 || s._Row >= _row || s._Col < 0 || s._Col >= _col)
    {
        return true;
    }//是为了判断已经越界则可以直接返回说明找到了出口
    else
    {
        return false;
    }
}
bool Maze::PassMaze()
{
    stack<Pos> s;
    s.push(_start);
    Pos seat;
    Pos Cur;
    while (!s.empty())
    {
        seat = s.top();
        Cur = seat;
        if (Cur._Row < 0 || Cur._Row >= _row || Cur._Col < 0 || Cur._Col >= _col)
        {
            return true;
        }
        _map[Cur._Row][Cur._Col] = 2;
        Cur._Row--;
        //向前走
        if (IsPass(Cur))
        {
            s.push(Cur);
            continue;
        }
        Cur = seat;
        Cur._Col--;//向左走
          if (IsPass(Cur))
            {
                s.push(Cur);
                continue;
            }
        Cur = seat;
        Cur._Col++;//向右走
            if (IsPass(Cur))
            {
                s.push(Cur);
                continue;
            }
        Cur = seat;
        Cur._Row++;//向后走
            if (IsPass(Cur))
            {
                s.push(Cur);
                continue;
            }
            Cur = seat;
            s.pop();
            _map[Cur._Row][Cur._Col] = 3;

    }
    return false;

    return false;
}
void FunTest()
{
    Maze p;
    p.SetMap();
    p.ShowMap();
    cout << endl;
    p.PassMaze();
    p.ShowMap();
    //p.PrintPath();
}
int main()
{
    FunTest();
    /*p.ShowMap();*/
    system("pause");
    return 0;
}