Snake

//新增功能:有計分，並且每吃3顆蘋果就會快100毫秒，最多會快到200毫秒刷新一次
#include <conio.h>
#include <iostream>
#include <vector>
#include <algorithm>
#include <time.h>
#include <windows.h>
using namespace std;

//define the direction button.
#define KEY_UP 72
#define KEY_DOWN 80
#define KEY_LEFT 75
#define KEY_RIGHT 77

//record the map, 1 for walls, 2 for snake, 3 for apple. 4 for blocks.
int length;
int wide;
int map[1000]={0};
int s_direction;  //record the direction of the snake.
int s_head ,s_tail; //record the coordinate of the head and the tail of the snake.
vector<int>s_body; //record the body (every joint) of the snake.
int apple; //record the coordinate of the apple.
int block ;
int score=0; //record the score you get.
int cut_time=0; //record the shrinked time.
int count_add=0; //record how many times the time shrink.


/*int rmap[1000];
void gotoxy(int xpos, int ypos)
{
  COORD scrn;
  HANDLE hOuput = GetStdHandle(STD_OUTPUT_HANDLE);
  scrn.X = xpos; scrn.Y = ypos;
  SetConsoleCursorPosition(hOuput,scrn);
} */

void set_size(){
    cout<<"Please type the length of the map that you want to play: "<<'\n';
    cin>>length;
    cout<<"Please type the wide of the map that you want to play: "<<'\n';
    cin>>wide;
    return;
}

void setpoint(int l , int w){
    for( int s = 1 ; s <= l*w ; s++ ){
        //cerr << s << endl;
        if(map[s] == 0 && map[s+1] == 0 && map[s+2] == 0
        && map[s-1] == 0 && map[s+3] == 0
        && map[s-l] == 0 && map[s+l] == 0
        && map[s-l+1] == 0 && map[s+l+1] == 0
        && map[s-l+2] == 0 && map[s+l+2] == 0 ){

            //set up the initial position of the snake.
            map[s]=2;
            map[s+1]=2;
            map[s+2]=2;

            //set up the coordinate of the head.
            s_body.push_back(s);
            s_body.push_back(s+1);
            s_body.push_back(s+2);
            s_head=s+2;
            //cerr << "snake positioned at " << s << endl;
            return;
        }
    }
    cout<<"cannot play,please change the size of the map!";
}
//draw maps with □■●.
void draw_map(int l , int w){
    system ( "cls" ); //cls means clear screen.
    cout<<"Scores: "<<score<<'\n';
    for( int d = 0 ; d < l*w ; d++ ){

        /*if (map[d] == rmap[d]) continue;
        rmap[d] = map[d];
        gotoxy(d%l, d/l+1);*/
        if( map[d] == 0 ){
            cout << "  ";
        }
        else if( map[d] == 3){
            cout << "●";
        }
        else if( map[d] == 4 ){
            cout << "□";
        }

        else{
            cout << "■";
        }
        if( d % l == l-1 ){
            cout << '\n';
        }
    }
}
//initialize the map.
void init_map( int l , int w ){
    /*for( int i = 0 ; i <= l*w-1 ; i++ ){
        rmap[i] = -1;
    } */

    // build up the walls.
    for( int i = 0 ; i <= l-1 ; i++ ){  //up
        map[i] = 1;
    }
    for(int i = 0 ; i <= l*(w-1) ; i+=l ){ //left
        map[i] = 1;
    }
    for(int i = l-1 ; i <= l*w-1 ; i+=l ){ //right
        map[i] = 1;
    }
    for(int i = l*(w-1) ; i <= l*w-1 ; i++ ){ //down
        map[i] = 1;
    }

    //set up the direction of the snake.
    s_direction = 1;

//  draw_map(l,w); //draw the initial map.
}

void new_apple(int l,int w){
    int x;
    while(1){
        x=rand()%(l*w); //choose a random square to put in a apple.
        if( map[x] == 0 ){ //the apple can only be put in the empty aquare.
            break;
        }
    }
    map[x] = 3; //set up the coordinate of the apple.

    if(count_add%3==0 && count_add!=0){
        if(cut_time>300){  //check if time reachs the limit of shrinked time.
            if(cut_time==450){
                return ;
            }
            cut_time += 50;
        }
        cut_time += 100; //if not, add more 100 minisecond in shrinked time.
    }
}

void new_block(int l , int w ){
    int y;
    while(1){
        y = rand() % ( l * w );
        if( map[y] == 0  && y !=  ( s_head + s_direction )){
            break;
        }
    }
    map[y]=4;
}


int main(void){
    srand( (int)time(NULL) ); //reset the random funtion in new_apple().
    int k; //record what button  you press.
    set_size();
    init_map(length,wide);
    setpoint(length,wide);
    new_apple(length,wide);
    draw_map(length,wide);

    do{  //Let the snake move:create a new head, and cut the tail.

        while(!kbhit()){ //while we don't press the botton.
            s_head = s_head + s_direction; // create a new head.

            //check if the snakes hits the wall.
            if(map[s_head]==1){
                cout<<"hit wall, game over";
                return 0;
            }


            /*vector<int>::iterator it = find(s_body.begin(),s_body.end(),s_head+s_direction);
            if(it !=s_body.end()){
                cout<<"bite self, game over";
                return 0;
            }*/

            //check if the snake bite itself.
            if(map[s_head+s_direction] == 2){
                cout<<"bite self, game over";
                return 0;
            }

            if(map[s_head+s_direction ] ==4){
                cout<<"hit a block, game over";
                return 0;
            }

            //chenk if the snake eats the apple.
            if(map[s_head]==3){
                new_apple( length , wide ); //if it does, put a new apple in the map.
                if(length*wide>=400 || score>=5){
                    new_block( length , wide );
                    new_block( length , wide );
                }
                else{
                    new_block( length , wide );
                }
                score++; //get one point.
                map[s_head]=2; //change the coordinate of the apple.
            }
            else{
                s_tail = s_body.front(); //take out the tail from the vector.

                s_body.erase ( s_body.begin () ); //cut the tail.

                map[s_tail] = 0;  //format the square of the old tail.
            }

            s_body.push_back( s_head ); // push the coordinate of the new head into the vector.

            map[s_head] = 2; //format the square of the new head.

            draw_map(length,wide) ; //redraw the map.

            Sleep( 200 - cut_time ); //stop for half a second to let our eyes be more comfortable.
        }

        k=_getch();
        //cout<<k , just for testing;

        if(k==224){ //that means we press the direction button.
            k=_getch(); //check which direction button we press.
            if(k==KEY_UP){
                s_direction=-length;
            }
            else if(k==KEY_DOWN){
                s_direction=length;
            }
            else if(k==KEY_LEFT){
                s_direction=-1;
            }
            else if(k==KEY_RIGHT){
                s_direction=1;
            }
        }

    } while( 1 ); //we can press "esc" button to stop this loop.

    return 0;
}