constructor(){

    this.len=1;

    this.body=[];

    this.body[0]=createVector(0,0)

    //this.body[0]=createVector(random(0,15),random(0,50));

    this.xdir=0;

    this.ydir=0;

  }

  setDir(x,y){

    this.xdir=x;

    this.ydir=y;

  }

  update(){

   let head =this.body[this.body.length-1].copy();

    this.body.shift();

    head.x+=this.xdir;

    head.y+=this.ydir;

    this.body.push(head);

  }

  grow(){

    let head =this.body[this.body.length-1].copy();

    this.len++;

    this.body.push(head);

  }

  endGame(){

     let x=  this.body[this.body.length-1].x;

    let y=  this.body[this.body.length-1].y;

     if(x>w-1|| x<0 || y>h-1 || y<0 ){

      return true;

    }

    for (let i=0;i<this.body.length-1;i++){

      if((this.body[i].x==x && this.body[i].y==y) )

         {

        fill(5*i,10+i,10*i);

        return  true;

      }

    }

   return false;

  }

  eat(pos){

    let x=  this.body[this.body.length-1].x;

    let y=  this.body[this.body.length-1].y;

    if( x== pos.x && y == pos.y){

      //print("food eat") was used for verifying whether the food was missing after the snake eats

      this.grow();

      return true;

    }else{

      return false;

    }

  }

  show(){

    for (let i=0;i<this.body.length;i++){

    fill(20*i,20*i,i);

    rect(this.body[i].x,this.body[i].y,1,1); 

     //circle(this.body[i].x,this.body[i],1)

    }

  }

}