There is a street lamp every 50 meters on Guoqing Road. How many meters did Huanhuan walk from the first street light to the 40th street light?
国庆路每隔50米有一盏路灯．欢欢从第一盏路灯走到第40盏路灯，一共走了多少米？
<gadget id="calculator">40 - 1</gadget>
<output>39</output>

<gadget id="calculator">50 * 39</gadget>
<output>1_950</output>

<result>1_950</result>