Install street lamps on both sides of a street in the city. The length of the street is 960 meters, and a street lamp is installed every 30 meters. If there are no street lamps at both ends of the road, how many street lamps are needed in total?
在城市一条大街两侧架设路灯，大街长960米，每隔30米设一个路灯，若路两端都不架设，共需路灯多少盏？
<gadget id="calculator">960 / 30</gadget>
<output>32</output>

<gadget id="calculator">32 - 1</gadget>
<output>31</output>

<gadget id="calculator">31 * 2</gadget>
<output>62</output>

<result>62</result>