A colored lantern is hung every 5 meters on a bridge. A total of 221 colored lanterns are hung from one end of the bridge to the other (one at each end of the bridge). How long is the bridge?
在一座桥上每隔5米挂一盏彩灯，从桥的一端到另一端共挂了221盏彩灯(桥的两端各挂一盏)，这座桥长多少米？
<gadget id="calculator">221 - 1</gadget>
<output>220</output>

<gadget id="calculator">220 * 5</gadget>
<output>1_100</output>

<result>1_100</result>