A, B, and C pass the ball. The first pass is started by A, and the ball is passed to B or C... After 4 passes, the ball just returns to A's hand, so how many different passes are there in total? Ball way?
甲、乙、丙三个人传球，第一次传球是由甲开始，将球传给乙或丙…经过4次传球后，球正好回到甲手中，那么一共有多少种不同的传球方式？
<gadget id="calculator">3 + 3</gadget>
<output>6</output>

<result>6</result>