The 11 handkerchiefs that have been washed are clamped on the rope with clips. The two sides of each handkerchief must be clamped with clips. The same clip clamps the two sides of two adjacent handkerchiefs. How many clips are needed in total?
洗好的11块手帕用夹子夹在绳子上，每一块手帕的两边必须用夹子夹住，同一个夹子夹住相邻的两块手帕的两边，一共要多少个夹子．
<gadget id="calculator">11 + 1</gadget>
<output>12</output>

<result>12</result>