Ferric Ion

题目描述Leopold is indeed a lucky fellow. He just won a huge estate in the lottery. The estate contains several grand buildings in addition to the main mansion, in which he intends to live from now on.

题目描述 The Romanian Ministry of Transport decides to upgrade the Romanian roads. Each road is bidirectional and directly connects two towns. No two towns are directly connected by more than one road.

题目描述 一群青蛙正在摧毁Byteotia所有的庄稼。一个叫Byteasar的农夫决定使用一种放在田里的奇特的”scarefrogs”来吓跑他们，所有的青蛙在跳跃过程中都尽量使自己离他们越远越好，即是让自己离最近的scarefrog越远越好。

题目描述 给出平面上的两个点集，如果其中一个点集可以通过扩大、缩小、旋转、翻转、移动等操作变换到另一个点集,那么我们就称这两个点集相似。