There are 6 pairs of socks of 3 different colors and different sizes in the drawer. To ensure that at least one pair of socks is complete, at least how many socks must be drawn.
抽屉里有3种不同颜色且每双大小都不同的袜子共6双，要保证摸出的袜子中至少有一双是完整的，则至少要摸出多少只袜子．
<gadget id="calculator">6 + 1</gadget>
<output>7</output>

<result>7</result>