基础迷宫问题-------------（图的BFS 题目取自算法竞赛入门）

#include <iostream>
#include <fstream>
#include <cstring>
#include <queue>
#include <stack>

using namespace std;

#define maxn  100

//0 set as blank, 1 set as wall

typedef struct{
    int i;
    int j;
}pos;

typedef struct{
    char pointer;
    int i;    
    int j;
}mov;

mov mov_flag[4]={{'r', 0, 1}, {'d', 1, 0}, {'l', 0, -1}, {'u', -1, 0} };    //reverse name see from father node

class maze{
public:
    maze(const int &m, const int &n):row(m), column(n){
            for(int i = 0; i <= row + 1; i++)
                for(int j = 0; j <= column + 1; j++)
                        map[i][j] = 1;
    
    } 
    int print_way(const int &m , const int &n, const int &out_m, const int &out_n);
private:
    friend ifstream & operator>>(ifstream &in, class maze &out);
    friend ostream  & operator<<(ostream &out, class maze &in);
    const int row;
    const int column;
    int map[maxn][maxn];
        
};

ifstream & operator>>(ifstream & in, class maze &out){
    for(int i = 1; i <= out.row; i++)
        for(int j = 1; j <= out.column; j++){
                in>>out.map[i][j];
        
        }
    return in; 
}

ostream & operator<<(ostream &out, class maze &in)
{
    for(int i = 0; i <= in.row + 1; i++){
        for(int j = 0; j <= in.column + 1; j++){
                out << in.map[i][j] << " ";
        
        }
        cout << endl;
    }
    return out; 
}

int maze::print_way(const int &m, const int &n, const int &out_m, const int &out_n)
{
    int dir[maxn][maxn];
    int  vis[maxn][maxn];
    memset(vis, 0, sizeof(vis));
    memset(dir, 0, sizeof(dir));
    pos tmp;

    if(map[m]
 == 1)
            return -1;
    queue<pos>store;
    tmp.i = m;
    tmp.j = n;
    store.push(tmp);
    while(!store.empty()){
            tmp = store.front();
            store.pop();
            int x, y;    
            for(int flag = 0; flag < 4; flag++){
                    vis[tmp.i][tmp.j] = 1;
                    x = tmp.i + mov_flag[flag].i;
                    y = tmp.j + mov_flag[flag].j;
                    if(0 == vis[x][y] && 0 == map[x][y]){
                            dir[x][y] = flag;  //set mov dir point to father
                            pos new_add;
                            new_add.i = x;
                            new_add.j = y;
                            store.push(new_add);            //push node into queue
                    }
            }
    
    }
    int i = out_m;
    int j = out_n;
    stack<char>way;
    while(i != m || j != n){
            int x, y, flag;
            flag = dir[i][j];
            way.push(mov_flag[flag].pointer);
            x = mov_flag[flag].i;
            y = mov_flag[flag].j;
            i -= x;
            j -= y;
    }
    while(!way.empty()){
            cout << " mov " << way.top() << "\n";
            way.pop();
    
    }
    return 0;
}

int main()
{
        maze test(10,10);
        ifstream  map("map", fstream::in);
        map  >> test;
        cout << test;
        test.print_way(1, 1, 10, 10);    
return 0;
}