CC turtle dig down

local blocks = 0
term.write("How many blocks down? :")
blocks = read()
function digAll()
	turtle.digUp()
	turtle.dig()
	turtle.digDown()
end
function gravel()
	if turtle.detect() then
		digAll()
	end
end
function One()
	for i = 1, blocks do
		inch()
	end
end
function inch()
	digAll()
	gravel()
	turtle.forward()
	digAll()
	gravel()
	turtle.down()
end
function turnR()
	turtle.turnRight()
	inch()
	turtle.turnRight()
end
function turnL()
	turtle.turnLeft()
	inch()
	turtle.turnLeft()
end
One()