编译器需要支持C++11

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <iterator>
#include <unistd.h>
#include <cstdio>
#include <fcntl.h>
#include <pthread.h>
#include <termios.h>
using namespace std;

class Posi{
  private:
    int y;
    int x;
    char c;
  public:
    int getY(void)const{return y;}
    int getX(void)const{return x;}
    char getC(void)const{return c;}
    void setY(int Y){y = Y;}
    void setX(int X){x = X;}
    void setC(char C){c = C;}

    Posi():y(0),x(0),c('H'){}
    Posi(int Y,int X,char C):y(Y),x(X),c(C){}
    //Posi(Posi& a):y(a.getY()),x(a.getX()),c(getC()){}
    ~Posi(){}
    bool operator==(const Posi& a)const{
      return (y==a.getY() && x==a.getX());
    }
    friend ostream& operator<<(ostream& out,const Posi& a);
};

ostream& operator<<(ostream& out,const Posi& a){
  out<< "\033["<<to_string(a.getY())<<";"
    <<to_string(a.getX())<<"H"<<a.c;
  return out;
}

class Snake{
  private:
    vector<Posi> body;
    int direction; //0:up 1:down 2:left 3:right
    bool crash;
  public:
    Snake():direction(1),crash(false){}
    Snake(char head):direction(1),crash(false){
      body.push_back(Posi{0,0,head});
    }
    Snake(Posi p):direction(1),crash(false){
      body.push_back(p);
    }
    int length(void)const{
      return body.size();
    }
    Posi getHead(void)const{
      return body[0];
    }
    void setDir(int dir){
      direction = dir;
    }

    bool isOver(void)const{
      return crash;
    }

    bool findP(Posi& a)const{
      return (find(body.begin(),body.end(),a)!=body.end());
    }
    void extendBody(Posi a){
      body.push_back(a);
    }
    void move(void){
      if(length()!=0){

        for(int i=body.size()-1,j = 0;i>0;--i){
          j = i-1;
          body[i].setY(body[j].getY());
          body[i].setX(body[j].getX());
        }

        if(direction==0 && body[0].getY()>1){
          body[0].setY(body[0].getY()-1);
          body[0].setX(body[0].getX());
        }else if(direction==1 && body[0].getY()<20){
          body[0].setY(body[0].getY()+1);
          body[0].setX(body[0].getX());
        }else if(direction==2 && body[0].getX()>1){
          body[0].setY(body[0].getY());
          body[0].setX(body[0].getX()-1);
        }else if(direction==3 && body[0].getX()<20){
          body[0].setY(body[0].getY());
          body[0].setX(body[0].getX()+1);
        }else{
          crash = true;
        }
        if(find(body.begin()+1,body.end(),body[0])!=body.end())
          crash = true;
      }
    }
    friend ostream& operator<<(ostream&,Snake&);

    ~Snake(){}
};

ostream& operator<<(ostream& out,Snake& a){
  out<< "\033[2J";
  if(a.crash==false){
    for(vector<Posi>::iterator it=(a.body).begin();it!=(a.body).end();++it)
      out<< *it;
  }else{
    out << "GameOver" << endl;
  }
  return out;
}

class TermScreen{
  private:
    Snake& snake;
    Posi& food;
  public:
    TermScreen(Snake& s,Posi& p):snake(s),food(p){}
    void feed(void){
      food.setX(5);
      food.setY(5);
      while(snake.findP(food)){
        food.setX((food.getX()+11)%20);
        food.setY((food.getY()+13)%20);
      }
      food.setC('a'+(food.getX()+food.getY())%26);
    }
    void eat(void){
      if(snake.getHead()==food){
        snake.extendBody(food);
        feed();
      }
      snake.move();
    }
    friend ostream& operator <<(ostream& out,TermScreen& t);
    ~TermScreen(){}
};

ostream& operator<<(ostream& out,TermScreen& t){
  out<< t.snake;
  out<< t.food;
}


void setStdoutNoBuff(ostream& out){
  out.setf(ios::unitbuf);
}
void setTerm(void){
  struct termios option;
  tcgetattr(0,&option);
  option.c_lflag &=~(ICANON|ECHO|ECHOE);
  tcsetattr(0,TCSANOW,&option);
}
void recoverTerm(void){
  struct termios option;
  tcgetattr(0,&option);
  option.c_lflag |=(ICANON|ECHO|ECHOE);
  tcsetattr(0,TCSANOW,&option);
}
/*
void setStdoutNoEcho(ostream& out){
}


void setStdinNoBuff(istream& in){
  in.setf(ios::unitbuf);
}
void setStdinNonBlock(void){
  int flags;
  flags = fcntl(STDIN_FILENO,F_GETFL);
  flags |=O_NONBLOCK;

  if(fcntl(STDIN_FILENO,F_SETFL,flags)<0){
    perror("fcntl");
    exit(EXIT_FAILURE);
  }
}*/
void *getDirection(Snake* s){
  char buf[10];
  while(1){
    int r = read(STDIN_FILENO,buf,1);
    if(r>0){
      if(buf[0]=='a')
        s->setDir(2);
      else if(buf[0]=='w')
        s->setDir(0);
      else if(buf[0]=='s')
        s->setDir(1);
      else if(buf[0]=='d')
        s->setDir(3);
    }
    if(s->isOver()){
      break;
    }
  }
  pthread_exit(NULL);
}

int main(void){
  setStdoutNoBuff(cout);
  setTerm();
//  setStdinNonBlock();
  Snake s;
  s.extendBody(Posi(5,6,'c'));
  s.extendBody(Posi(5,5,'d'));
  s.extendBody(Posi(5,4,'a'));
  s.extendBody(Posi(4,4,'t'));
  Posi food(4,9,'f');
  
  TermScreen t(s,food);
  cout << t;
  pthread_t thread_id;
  pthread_create(&thread_id,NULL,(void*(*)(void*))getDirection,&s);
  while(1){
    t.eat();
    cout << t;
    if(s.isOver()){
      break;
    }
    sleep(1);
  }
  pthread_join(thread_id,NULL);
  recoverTerm();
  return 0;
}