The altitude of land A is +100 meters, and the altitude of land B is -50 meters. How much is the difference between the heights of land A and land B?
甲地的海拔高度是+100米，乙地的海拔高度是-50米，甲、乙两地高度相差多少米
<gadget id="calculator">100 - (-50)</gadget>
<output>150</output>

<result>150</result>