题目链接:E - New Year and the Acquaintance Estimation 题解参考: Havel–Hakimi algorithm 和 Erdős–Gallai theorem 按照后面那个定理说的,枚举$k∈[1,n]$,对于每一个$k$,计算出向等式两边加入$a_{n+1}$的合法范围,最后所有范围求交即可 最后按照前面那个定理说的,枚举最终区间的时候,对于合法真正的$a_{n+1}$进行输出即可 比赛的时候没看见后面那个定理,推了半天 --------------…
主题链接:pid=2454">http://acm.hdu.edu.cn/showproblem.php?pid=2454 Problem Description Wang Haiyang is a strong and optimistic Chinese youngster. Although born and brought up in the northern inland city Harbin, he has deep love and yearns for the bound…
Graph Reconstruction Time Limit: 2 Seconds Memory Limit: 65536 KB Special Judge Let there be a simple graph with N vertices but we just know the degree of each vertex. Is it possible to reconstruct the graph only by these information? A sim…
http://acm.hdu.edu.cn/showproblem.php?pid=3037 Lucas定理模板. 现在才写,noip滚粗前兆QAQ #include<cstdio> #include<cstring> #include<algorithm> using namespace std; typedef long long ll; int jc[100003]; int p; int ipow(int x, int b) { ll t = 1, w = x;…
Codeforces Round #258 (Div. 2) Devu and Flowers E. Devu and Flowers time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Devu wants to decorate his garden with flowers. He has purchased n boxes…