There are 4 students who want to play a table tennis match, and every two students play a game, how many games will be played in total?
有4名同学要进行一场乒乓球比赛，每两个同学打一场球，一共要打多少场？
<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>