#include <iostream>

#include <conio.h>

#include <windows.h>

#include <time.h>

int g_Dir = ;

#define UP         0

#define DOWN  1

#define LEFT       2

#define RIGHT   3

struct FOOD

{

    int X = ;

    int Y = ;

    bool State = ;

}Food;

//方向控制

void SnekeMove()

{

    if (::GetAsyncKeyState(VK_UP) & )

        g_Dir = ;

    if (::GetAsyncKeyState(VK_DOWN) & )

        g_Dir = ;

    if (::GetAsyncKeyState(VK_LEFT) & )

        g_Dir = ;

    if (::GetAsyncKeyState(VK_RIGHT) & )

        g_Dir = ;

}

//主函数

int main()

{

    srand((unsigned int)time(NULL));

    int W = ;

    int H = ;

    int Len = ;

    int Map[ * ] = {  };

    int Snake[] = {  };

    //Snake[0] = 2;//为蛇头

    for (int i = ; i < Len; i++)

    {

        Snake[i] = Len - i - ;

    }

    Food.X = W / ;

    Food.Y = H / ;

    Map[Food.Y * W + Food.X] = ;

    const char *SNAKE[] = { "  ", "■" ,"★"};

    while (true)

    {

        system("cls");

        for (int i = ; i < Len; i++)

        {

            // 2 1 0

            // 1 1 1

            // 3 2 1

            // 0 1 1 1

            //这里需要注意

            Map[Snake[i]] = ;

        }

        Map[Food.Y * W + Food.X] = ;

        if (Map[Snake[]] == Map[Food.Y * W + Food.X])

        {

            Map[Food.Y * W + Food.X] = ;

            do

            {

                bool FoodState = false;

                Food.X = rand() % W;

                Food.Y = rand() % H;

                for (int i = ; i < Len; i++)

                {

                    if (Map[Food.Y * W + Food.X] != Map[Snake[i]])

                    {

                        FoodState = true;

                    }

                }

                if (FoodState)

                {

                    Map[Food.Y * W + Food.X] = ;

                    break;

                }

            } while (true);

            Len++;

        }

        for (int i = ; i < H; i++)

        {

            for (int j = ; j < W; j++)

            {

                //蛇头在地图上的坐标

                if (i * W + j == Snake[])

                {

                    if (i == H -  || j == W - )

                    {

                        //撞墙

                        system("pause");

                        return ;

                    }

                }

            }

        }

        for (int i = ; i < H; i++)

        {

            for (int j = ; j < W; j++)

            {

                std::cout << SNAKE[Map[i * W + j]];

            }

            std::cout << std::endl;

        }

        std::cout << std::endl;

        //for (int i = 0; i < Len; i++)

        //{

        //    std::cout << Snake[i]<<"  ";

        //}

        //std::cout << std::endl;

        std::cout <<"蛇的长度为 : "<<Len<<std::endl;

        memset(Map, , sizeof(Map));

        SnekeMove();

        for (int i = Len; i > ; i--)

        {

            // 2 1 0

            //默认往右挪

            // 2 2 1 0

            //后面++

            // 3 2 1 0

            //完成一次移动

            Snake[i] = Snake[i - ];

            /*

            比如往下

            // 3 2 1 0

            // 23 3 2 1 0

            */

        }

        if (g_Dir == UP)

        {

            Snake[] -= W;

        }

        if (g_Dir == DOWN)

        {

            Snake[] += W;

        }

        if (g_Dir == LEFT)

        {

            Snake[]--;

        }

        if (g_Dir == RIGHT)

        {

            Snake[]++;

        }

        Sleep();

    }

    //https://www.bilibili.com/video/av29007126/?spm_id_from=333.788.videocard.1

    system("pause");

    return ;

}