function refuel()
	if turtle.getFuelLevel() < 10 then
		turtle.select(1)
		turtle.refuel(1)
	end
end

function squareMine(size)
	for x=1, size do
		for y=1, size-1 do
			refuel()

			turtle.dig()
			forward()
		end

		if not (x == size) then
			if (x % 2 == 0) then
				turtle.turnRight()
				turtle.dig()
				forward()
				turtle.turnRight()
			else
				turtle.turnLeft()
				turtle.dig()
				forward()
				turtle.turnLeft()
			end
		end
	end
end

function forward()
	while not turtle.forward() do
		turtle.dig()
		turtle.attack()
		print("Forward movement obstructed")
	end
end

function down()
	while not turtle.down() do
		turtle.digDown()
		print("Down movement obstructed")
	end
end

args = {...}
triangleSize = args[1]

for v=1, triangleSize-1 do
	size = ((triangleSize - v) * 2) + 1
	squareMine(size)
	refuel()
	if size % 2 == 0 then
		turtle.turnLeft()
		forward()
		turtle.turnLeft()
		forward()
		turtle.digDown()
		down()
	else
		turtle.turnRight()
		forward()
		turtle.turnRight()
		forward()
		turtle.digDown()
		down()
	end
end