There are 6 red balls and 6 yellow balls in the pocket. In the pocket, at least touch as many balls as possible to ensure that there are two of the same color.
口袋里有红球黄球各6个，在放口袋里，至少摸多少个球就可以保证有两个颜色相同的．
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<result>3</result>