A bundle of wires is 1000 meters long, first 156 meters are used, and then 395 meters are used. How many meters is this bundle of wires shorter than the original?
一捆电线长1000米，先用去156米，又用去395米．这捆电线比原来短了多少米？
<gadget id="calculator">156 + 395</gadget>
<output>551</output>

<result>551</result>