Congcong, Mingming, Xiaoqiang and Xiaohua go boating together. How many different ways can two people take a boat?
聪聪、明明、小强和小华一起去划船，2人坐一条船，可以有多少种不同的方法？
<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<result>6</result>