go

distance = 100;
traveled = 0;
slot = 0;

while traveled < distance do
  if turtle.getFuelLevel() <= 0 then
    turtle.select(1);
    turtle.refuel(1);
  else
    turtle.dig();
    turtle.forward();
    traveled = traveled+1;

    if traveled%50 == 0 then
      slot = 5;
      while slot <= 16 do
        turtle.select(slot);
        slot = slot+1;
        if turtle.compareTo(2) or turtle.compareTo(3) or turtle.compareTo(4) then
          turtle.drop(64);
        end
      end
    end
  end
end