class program {

void turn(n) { iterate(n) turnleft(); }

void recuerdaDireccion(n)
{
   if(notFacingNorth)
   {
      turnleft();
      recuerdaDireccion(n);
      turn(3);
   }else
   {
       divisible(n);
       while(notFacingNorth)
         turnleft();
   }
}

void compara(n)
{
   if (notNextToABeeper)
   {
       iterate(n)
          putbeeper();
   }
   else
   {
      while(notFacingNorth)
         turnleft();
      quita(n);
      if (facingNorth)
      {
         while(nextToABeeper)
            pickbeeper();
         iterate(n)
            putbeeper();
      }
      else
      {
         while(notFacingNorth)
            turnleft();
         quita(n);
      }
      while(leftIsClear || rightIsClear || frontIsClear)
         turnleft();
   }
}

void busca(n)
{
   if (frontIsClear || rightIsClear || leftIsClear)
   {
       recuerdaDireccion(n);
   }
   else
   {
      compara(n);
   }
}

void quita(n)
{
      iterate(n)
      {
         if (facingNorth)
         {
            if (nextToABeeper)
               pickbeeper();
            else
            {
               turnleft();
               putbeeper();
            }
         }
         else
         {
            putbeeper();
         }
      }
}

void divisible(n)
{
      quita(n);
      if (notNextToABeeper)
      {
          iterate(4)
          {
             if (frontIsClear)
             {
                move();
                busca(succ(n));
                turn(2);
                move();
                turn(2);
             }
             turnleft();
          }
          while(notFacingNorth)
            turnleft();
      }else
      {
         if (facingNorth)
         {
            divisible(n);
         }
         else
         {
            while(notFacingNorth)
              turnleft();
         }
      }
      quita(n);
}

program() {
       iterate(4)
       {
         if (frontIsClear)
         {
            move();
            busca(1);
            turn(2);
            move();
            turn(2);
         }
         turnleft();
      }
    turnoff();
}

}