There are 6 players who want to play table tennis. If every 2 players have to play a game, how many games will be played in total?
有6名运动员要进行乒乓球比赛，如果每2名运动员之间都要进行一场比赛，一共要进行多少场比赛？
<gadget id="calculator">6 - 1</gadget>
<output>5</output>

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

<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>