Someone puts a set of Go chess in a box, and then molds 3 chess pieces from the box each time. How many times can he touch at least to ensure that the chess pieces taken out of 2 times are the same.
某人把一副围棋混装在一个盒子里，然后每次从盒子中模出3枚棋子，他至少摸多少次，才能保证其中有2次取出的棋子是相同的．
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<result>5</result>