There is a box containing 20 socks of three colors: blue, white, and red. To match three pairs of socks, at least how many times must be touched.
有一个盒子里装有蓝、白、红三种颜色袜子各20只，要配三双袜子，至少要摸多少次．
<gadget id="calculator">4 + 2 + 2</gadget>
<output>8</output>

<result>8</result>