4 red balls and 4 yellow balls are placed in an opaque plastic bag. Every time you touch a ball from the bag, you must ensure that you must touch two balls of the same color, and you must touch at least how many balls each time.
一个不透明的塑料袋里放4个红球和4个黄球．每次从袋中摸一个球，要保证一定摸到两个同色的球，每次至少要摸多少个球．
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<result>3</result>