quarry

function refuel()
  if turtle.getFuelLevel() < 1 then
    turtle.select(16)
    turtle.refuel(1)
  end
end

refuel()

function mineForward()
  for i=1,15,1 do
    refuel()
    turtle.dig()
    turtle.forward()
  end
end

direction = false

function mineLayer()
  for i=1,15,1 do
    --false is right, true is left
    mineForward()
    refuel()
    if direction == false then
      turtle.turnRight()
      turtle.dig()
      turtle.forward()
      turtle.turnRight()
      direction = not direction
    else
      turtle.turnLeft()
      turtle.dig()
      turtle.forward()
      turtle.turnLeft()
      direction = not direction
    end
  end
  mineForward()
  turtle.digDown()
  turtle.down()
  turtle.turnRight()
  turtle.turnRight()
end

function layerDown()
  for i=1,userYValue-5,1 do
    mineLayer()
  end
end

print("Enter the Y coordinate of the turtle: ")
userYValue = read()

layerDown()