There are gloves of the same size but different colors in a cloth bag. The colors are black, red, blue, and yellow. At least how many gloves must be found to ensure that there are 3 pairs of the same color.
一只布袋中装有大小相同但颜色不同的手套，颜色有黑、红、蓝、黄四种，最少要摸出多少只手套才能保证有3副同色的．
<gadget id="calculator">5 + 2 + 2</gadget>
<output>9</output>

<result>9</result>