#include<iostream>
#include<fstream>
using namespace std;

const int MAX = 10;
int n, m, k;
int board[MAX][MAX];
int best[MAX][MAX];
int dirs = 0;  //转弯次数
int min = 100000;   //最少转弯次数
int count = 0;  //不同的最少转弯道路数
struct Point
{
    int x, y;
};
Point luo;
Point ye;

int dx[8] = {1, 0, -1, 0, 1, 1, -1, -1}; //八个方向
int dy[8] = {0, 1, 0, -1, 1, -1, 1, -1};

bool ok(int x, int y)
{
    if(x>0 && y>0 && x<=n && y<=m && board[x][y]==0) //在迷宫内且未走到封闭房间
        return true;
    else
        return false;
}

void save()
{
    for(int i=1; i<=n; i++)
        for(int j=1; j<=m; j++)
            best[i][j] = board[i][j];
}

void backtrack(int x, int y, int dep, int di)
{ 
    if(dep == n*m-k && x == ye.x && y == ye.y && dirs<=min)
    {          //如果所有方格走遍，且到达朱丽叶位置，且转弯次数<=最优转弯次数
        if(dirs < min)  //如果<最优转弯次数
        {
            min = dirs;
            count = 1;   //重新记录道路数
            save();
        }
        else  
            count++;  //否则道路数增加
        return;
    }
    if(dep == n*m-k && x == ye.x && y == ye.y && dirs>min)
        return;
    for(int i=0; i<8; i++)  //可走的八个方向
    {
        int nextx = x + dx[i];  //计算下一步坐标
        int nexty = y + dy[i];
        if(ok(nextx, nexty))  //如果下一步可行
        {   
            board[nextx][nexty] = dep + 1;  
            if(dep>1 && di != i)  //第一步不算转弯，如果方向不同，转弯次数增加
                dirs++;

            backtrack(nextx, nexty, dep+1, i);

            board[nextx][nexty] = 0;  //回溯
            if(dep>1 && di != i)
                dirs--;
        }
    }
}

int main()
{
    ifstream fin("罗密欧.txt");
    cout << "\n输入行数n：";
    fin >> n;  cout << n;
    cout << "\n输入列数m：";
    fin >> m;  cout << m;
    cout << "\n输入封闭的房间数：";
    fin >> k;  cout << k << endl;
    int i;
    memset(board, 0, sizeof(board));
    int x, y;
    for(i=1; i<=k; i++)
    {
        cout << "输入第" << i << "个封闭房间所在的行号和列号：";
        fin >> x >> y;
        cout << x << " " << y << endl;
        board[x][y] = -1;  //标记封闭房间
    }
    cout << "输入罗密欧位置：";
    fin >> luo.x >> luo.y;
    cout << luo.x << " " << luo.y;

    cout << "\n输入朱丽叶位置：";
    fin >> ye.x >> ye.y;
    cout << ye.x << " " << ye.y;

    board[ luo.x ][ luo.y ] = 1;
    backtrack(luo.x, luo.y, 1, 0);
    cout << "\n最少转弯次数为：" << min;
    cout << "\n不同的最少转弯道路数为：" << count;
    cout << "\n一条路径为：\n";
    for(i=1; i<=n; i++)
    {
        for(int j=1; j<=m; j++)
            cout << best[i][j] << "\t";
        cout << endl;
    }
    cout << endl << endl;
    return 0;
}