local size = {...}
if size ~= 3 then
  print("I need an x, y,")
  print("and z coordinate.")
  print("Try again.")
  term.clear()
  term.setCursorPos(1,1)
  error()
else
  print("Digging a hole...")
end

function move(count)
  for z = 1, count do
    turtle.forward()
  end
end

function next(length, width)
  if width % 2 == 0 then
    turtle.turnRight()
    turtle.move(width - 1)
    turtle.turnRight()
  else
    turtle.turnRight()
    turtle.turnRight()
    move(length - 1)
    turtle.turnRight()
    move(width - 1)
    turtle.turnRight()
  end
  turtle.down()
end

function home(depth)
  for i = 1, depth do
    turtle.up()
  end
  turtle.back()
  print("Hole complete. :)")
end

for i = 1, size[3] do
  for j = 1, size[2] do
    for k = 1, (size[1] - 1) do
      turtle.digDown()
      turtle.forward()
    end
    turtle.digDown()
    if j == size[2] then
      next(size[1], size[2])
    elseif j % 2 == 0 then
      turtle.turnLeft()
      turtle.forward()
      turtle.turnLeft()
    else
      turtle.turnRight()
      turtle.forward()
      turtle.turnRight()
    end
  end
end

Home(size[3])