There are 8 table tennis players participating in a table tennis competition. The competition adopts a round-robin competition. Every two players have to play one game. How many games should be organized?
有8名乒乓球选手参加乒乓球比赛，比赛采取循环赛，每两名运动员都要赛一场，应该组织多少场比赛．
<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">8 * (7/2)</gadget>
<output>28</output>

<result>28</result>