platform

function forwardorbust()
  while not turtle.forward() do
    turtle.dig()
    end
  end

turtle.select(1)
for i=1,4 do
  for k=1,4 do
    for j=1,i*2-1 do
      turtle.placeDown()
      forwardorbust()
      end
    turtle.turnLeft()
    if i == 3 then
      turtle.turnLeft()
      turtle.select(2)
      turtle.place()
      turtle.select(1)
      turtle.turnRight()
      end
    end
    turtle.turnRight()
    forwardorbust()
    turtle.turnRight()
    forwardorbust()
    turtle.turnLeft()
    turtle.turnLeft()
  end