片语
stack recursion circumcircle checking栈递归法检测外接圆
tracks circumcircle轨迹外接圆
circumcircle e外切圆
circumcircle of a triangle三角形的外接圆
circumcircle of a polygon多边形的外接圆
circumscribed circle[数] 外接圆;[数] 外切圆
circumcircle correspondence外接圆对应
Rule of empty circumcircle空外接圆準则
Circumcircle Example Walkthrough外接圆范例攻略
excircle外圆,外切圆