Bridge

local tArgs = {...}
if #tArgs ~= 1 then
    print("Please")
    return
end

local x = tonumber(tArgs[1])

if x < 0 then
    print("Invalid (negative) dimensions")
    return
end

local fuel = turtle.getFuelLevel()
local bridgeLenght = x+x+x
while fuel < bridgeLenght do
    turtle.select(16)
    if not turtle.refuel(1) then
        print("not enough Fuel")
        return
    turtle.select(1)
    end
end

while bridgeLenght < fuel do
    for i = x,1,-1 do
        turtle.forward()
        turtle.placeDown()
        turtle.turnRight()
        turtle.forward()
        turtle.placeDown()
       turtle.place()
       turtle.turnLeft()
       turtle.turnLeft()
       turtle.forward()
       turtle.forward()
       turtle.forward()
       turtle.placeDown()
       turtle.place()
       turtle.turnRight()
       turtle.turnRight()
       turtle.forward()
       turtle.turnLeft()
    end
end

if turtle.getItemCount() == 0 then
    turtle.select(2)
    if turtle.getItemCount() == 0 then
        turtle.select(3)
        if turtle.getItemCount() == 0 then
            turtle.select(4)
            if turtle.getItemCount() == 0 then
                turtle.select(5)
                if turtle.getItemCount() == 0 then
                    turtle.select(6)
                    if turtle.getItemCount() == 0 then
                        turtle.select(7)
                        if turtle.getItemCount() == 0 then
                            turtle.select(8)
                            if turtle.getItemCount() == 0 then
                                turtle.select(9)
                                if turtle.getItemCount() == 0 then
                                    turtle.select(10)
                                    if turtle.getItemCount() == 0 then
                                        turtle.select(11)
                                        if turtle.getItemCount() == 0 then
                                            turtle.select(12)
                                            if turtle.getItemCount() == 0 then
                                                turtle.select(13)
                                                if turtle.getItemCount() == 0 then
                                                    turtle.select(14)
                                                    if turtle.getItemCount() == 0 then
                                                        turtle.select(15)
                                                        if turtle.getItemCount() == 0 then
                                                            print("Building Materials Missing")
                                                            return
                                                        end
                                                    end
                                                end
                                            end
                                        end
                                    end
                                end
                            end
                        end
                    end
                end
            end
        end
    end
end