Two circles can generate up to 4 arc segments; three circles can generate up to 12 arc segments; then 10 circles can generate up to how many arc segments.
两个圆，最多可以生成4条弧线段；三个圆最多生成12条弧线段；则10个圆，最多生成的弧线段是多少条．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">2 * 9 * 10</gadget>
<output>180</output>

<result>180</result>