摘要：
For a connected undirected weighted graph G, MST (minimum spanning tree) is a subgraph of G that contains all of G's vertices, is a tree, and sum of i 阅读全文
摘要：
A point belongs to a triangle if it lies inside the triangle or on one of its sides. Two triangles are disjoint if there is no point on the plane that 阅读全文
摘要：
Dima the hamster enjoys nibbling different things: cages, sticks, bad problemsetters and even trees! Recently he found a binary search tree and instin 阅读全文
摘要：
One day Natalia was walking in the woods when she met a little mushroom gnome. The gnome told her the following story: Everybody knows that the mushro 阅读全文
摘要：
I guess there's not much point in reminding you that Nvodsk winters aren't exactly hot. That increased the popularity of the public transport dramatic 阅读全文
摘要：
Sherlock Holmes found a mysterious correspondence of two VIPs and made up his mind to read it. But there is a problem! The correspondence turned out t 阅读全文
摘要：
You have been offered a job in a company developing a large social network. Your first task is connected with searching profiles that most probably be 阅读全文
摘要：
题意：给定N点，M边，求添加最少的边使之变为连通图的方案数。 思路：注意题目给出的M边可能带环，即最后生成的不一定是一棵树。但是影响不大。根据矩阵树定理，我们知道生成树的数量=N^(N-2)，即点数^(连通数-2)。 此题把已经连通的看成一个整体，就可以得到数量为N^(cnt-2)，然后考虑连通块内 阅读全文
摘要：
Nowadays all circuses in Berland have a round arena with diameter 13 meters, but in the past things were different. In Ancient Berland arenas in circu 阅读全文
摘要：
De Prezer loves rectangles.He has a n × m rectangle which there is a number in each of its cells. We show the number in the j - th column of the i - t 阅读全文