test

function dropAllLeft()
  turtle.turnLeft()
  for i=1,16 do
    turtle.select(i)
    turtle.drop()
  end
  turtle.turnRight()
end

function dropAllDown()
  for i=1,16 do
    turtle.select(i)
    turtle.dropDown()
  end
end

while turtle.detect() do
  turtle.dig()
end
dropAllDown()