题目链接:http://codeforces.com/problemset/problem/1167/C 题意:大概就是分成几个小团体,给每个人用1 - n编号,当对某个人传播消息的时候,整个小团体就知道这个消息,输出 分别对1 - n编号的某个人传递消息时,有多少人知道这个消息. 思路:题目可理解为输出1 - n每个号码所在团体总人数,利用并查集不断向集合添加成员,记录每个集合的人数,保存在根节点的sum[]中,查询每个节点的根节点,输出根节点sum[]: 总结:初看好像是简单并查集,于是敲了…

News Distribution 题意 大概就是分成几个小团体,给每个人用1 - n编号,当对某个人传播消息的时候,整个小团体就知道这个消息,输出 分别对1 - n编号的某个人传递消息时,有多少人知道这个消息. Input 第一行n和m(n,m<=5*10^5) 接着m行,每行一个ki,接着ki(0<=ki<=n)个数,代表这个ki个人在一个QQ群里 Output 输出n个数,第i个代表,第ai个人知道谣言后,最多可以传播给几个人 Example Input 7 5 3 2 5 4 0…

题目: In some social network, there are nn users communicating with each other in mm groups of friends. Let's analyze the process of distributing some news between users. Initially, some user xx receives the news from some source. Then he or she sends…

D.Distribution of Days The Gregorian calendar is internationally the most widely used civil calendar. It is named after Pope Gregory XIII, who introduced it in October 1582. In the Gregorian calendar, there are 28 days in February in a common year an…

A - Jzzhu and Cities CodeForces - 449B 题意:n座城市,m条路,k条铁路啥的吧,然后要求最多能删多少条铁路保持1到$n$的最短路不变. 思路:因为铁路是从1出发的.所以能删的铁路有该铁路长度不等于1到该节点的最短路的,相等的时候,如果该节点的入度非1,也可以删去. #include <cstdio> #include <cstring> #include <algorithm> #include <vector> #in…

A - Luggage DistributionTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87493#problem/A Description All provident tourists know about low-cost airlines. Those who used them at least once also know th…

http://codeforces.com/contest/798/problem/D http://blog.csdn.net/yasola/article/details/70477816 对于二维的贪心我们可以先让它变成其中一维有序,这样只需要重点考虑另一维,就会简单很多. 首先,对于题目要求的选择元素之和两倍大与所有元素之和,我们可以转化为选择元素之和大于剩下的.然后我们可以将下标按照a从大到小排序.然后选择第一个,之后每两个一组,选择b大的一个,如果n是偶数再选择最后一个. 至于这样写…

D. Mike and distribution time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Mike has always been thinking about the harshness of social inequality. He's so obsessed with it that sometimes it…

Mike has always been thinking about the harshness of social inequality. He's so obsessed with it that sometimes it even affects him while solving problems. At the moment, Mike has two sequences of positive integers A = [a1, a2, ..., an] and B = [b1, …

题意:给你两个数列a,b,你要输出k个下标,使得这些下标对应的a的和大于整个a数列的和的1/2.同时这些下标对应的b //题解:首先将条件换一种说法,就是要取floor(n/2)+1个数使得这些数大于剩下的数.然后想到两种取法,一种是排好序选前半段.令一种取法是两个两个分组,每组取大的那个.//然后就可以(很困难地)想到一种巧妙的取法,先用一个结构体保存a,b,idx,按照a从大到小排序,先取第一个,再对剩下的每两个一组取其中b更大的.这样保证了被选出//的b一定大于剩下的b,也就满足了条件.然…