fell

local running = false

function cutUp()
        turtle.digUp()
        turtle.up()
end

function down()
        turtle.down()
end

function cutTree()
turtle.dig()
turtle.forward()
repeat
cutUp()
until turtle.detectUp() == false
repeat
down()
until turtle.detectDown() == true
end

function run()
 while running == true do
  if turtle.getFuelLevel() < 20 then
   turtle.refuel(1)
  end
  p1,p2 = turtle.inspect()
  if p2.name == "minecraft:stone" then
   turtle.turnRight()
   turtle.forward()
   turtle.forward()
   turtle.forward()
   turtle.forward()
   turtle.turnRight()
  end
  if p2.name == "minecraft:cobblestone" then
   turtle.turnLeft()
   turtle.forward()
   turtle.forward()
   turtle.forward()
   turtle.forward()
   turtle.turnLeft()
  end
  if p2.name == "minecraft:brick_block" then
   print("Loop complete... returning home.")
   turtle.turnRight()
   for i=1,20 do
    turtle.forward()
   end
   turtle.turnRight()

   if p2.name == "minecraft:sapling" then
    return
   end
  end
  cutTree()
  repeat
  turtle.forward()
  print(turtle.getFuelLevel())
  until turtle.detect() == true
 end
end

function start()
repeat
turtle.forward()
until turtle.detect() == true
running = true
run()
end

start()