// snake variables

int snakesize=1; //size of the snake

int MAXLENGTH=10;

int headx[]=new int[MAXLENGTH]; //xlocation

int heady[]=new int[MAXLENGTH]; //ylocation

int i;

//FOOD VARIABLES

int yumx=(round(random(49))+1)*10;

int yumy=(round(random(49))+1)*10;

  //SPEED

int speed;         

int xspeed,yspeed; 

void setup (){

  

  size (500,500);

  

  headx[0] = 250;

  heady[0] = 250;

  // SNAKE HEAD BEGINS UNMOVING.

  speed=1;           

  xspeed=0;     

  yspeed=0;

}

void draw (){

  background (0);

  

  fill(255,0,0);

  ellipseMode(CENTER);

  ellipse(yumx,yumy,15,15);

  

   for(int i =0; i < snakesize; i++){

   //tail

   fill(200, 20, 200);

   rectMode(CENTER);

   rect(headx[i],heady[i],20,20);

   headx[i]=headx[i]+xspeed;

   heady[i]=heady[i]+yspeed;

   }

// FOOD

 if(snakesize<headx.length)

 {

 if (headx[0]>=yumx-20 && headx[0]<=yumx+20 && heady[0]>=yumy-20 && heady[0]<yumy+20)

 {

    yumx=(round(random(49))+1)*10;

    yumy=(round(random(49))+1)*10;

  

  snakesize++;

  

  if (i!=1)

  {

  headx[snakesize -1] = headx[snakesize - 2] - 0;

  heady[snakesize -1] = heady[snakesize - 2] - 20;

  }

  

 }

 }

}

void keyPressed()

{

   // ARROW KEYS OR LETTER KEYS PRESSED.

   // RIGHT & LEFT HAND CONTROLS.

  

  if(keyCode==UP || key == 'w')

      { 

        xspeed=0;

        yspeed=-2;

      }

  else if(keyCode==DOWN || key =='s')

       { 

         xspeed=0;

         yspeed=2;

       }

  else if(keyCode==LEFT || key=='a')

        { 

          xspeed=-2;

          yspeed=0;

        }

  else if(keyCode==RIGHT || key =='d')

        { 

          xspeed=2;

          yspeed=0;

        }    

}