--check fuel level
local function checkFuel()
    if turtle.getFuelLevel() == 0 then
        turtle.select(16)
        turtle.refuel(1)
        return true
    end
    return false
end



--main

for i = 1, 29, 1 do
    for j = 1, 22, 1 do
        turtle.placeDown()
        checkFuel()
        turtle.forward()
    end
    if i % 2 == 1 then
        turtle.turnRight()
        checkFuel()
        turtle.forward()
        turtle.turnRight()
    end
    if i % 2 == 0 then
        turtle.turnLeft()
        checkFuel()
        turtle.forward()
        turtle.turnLeft()
    end
end