There are 4 red balls and 4 white balls in the box, at least how many balls should Xiao Fang draw to ensure that there are two balls of the same color.
盒子里有4个红球和4个白球，小方至少要摸出多少个球，才能保证有两个相同颜色的球．
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<result>3</result>