There are 9 steps from the first floor to the second floor. Xiaogang can climb one or two steps each time. Ask: How many different ways are there in total?
从一楼到二楼共有9级台阶，小刚每次可以登上一级或二级，问：一共有多少种不同的登楼方法？
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">5 + 8</gadget>
<output>13</output>

<gadget id="calculator">8 + 13</gadget>
<output>21</output>

<gadget id="calculator">13 + 21</gadget>
<output>34</output>

<gadget id="calculator">21 + 34</gadget>
<output>55</output>

<result>55</result>