Three people, Li Mei, Wang Fang, and Zhang Qin, each made a phone call once, how many times did they make phone calls in total?
李梅、王芳、张琴3个人，每两人通一次电话，一共通了多少次电话．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">3 * 1</gadget>
<output>3</output>

<result>3</result>