Another fun Greedy problem to work on: we simply go from first to second last person, as long someone is odd, we distribute bread to her and her next. #include <vector> #include <iostream> using namespace std; int main() { int N; cin >>…

You are given N processors and M jobs to be processed. Two processors are specified to each job. To process the job, the job should be allocated to and executed on one of the two processors for one unit of time. If K jobs are allocated to a processor…

F. Bear and Fair Set time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Limak is a grizzly bear. He is big and dreadful. You were chilling in the forest when you suddenly met him. It's very u…

一.公平锁 1.为什么有公平锁 CPU在调度线程的时候是在等待队列里随机挑选一个线程,由于这种随机性所以是无法保证线程先到先得的(synchronized控制的锁就是这种非公平锁).但这样就会产生饥饿现象,即有些线程(优先级较低的线程)可能永远也无法获取cpu的执行权,优先级高的线程会不断的强制它的资源.那么如何解决饥饿问题呢,这就需要公平锁了. 产生饥饿的另一个原因是:某个线程占据资源不释放,那其他需要该资源的线程只能处于无限等待中.在这里我们主要解决第一种饥饿问题. 2.什么是公平锁 公平锁…

Fair Scheduler 队列设置经验总结 由于公司的hadoop集群的计算资源不是很充足,需要开启yarn资源队列的资源抢占.在使用过程中,才明白资源抢占的一些特点.在这里总结一下. 只有一个队列的资源小于设置的 最小资源时,才有可能启动资源抢占. 所有的资源队列的最小资源之后小于等于集群的资源总量都是合理的.如果最小资源之和大于集群的资源总量,同时又开启了资源抢占模式,那么资源调度就会不停的处于资源抢占的模式(这样的逻辑当然是不合理的了). 所有队列的最大资源配置之和可以大于集群的资源总…

题目传送门:https://www.hackerrank.com/challenges/unique-colors 感谢hzq大神找来的这道题. 考虑点分治(毕竟是路经统计),对于每一个颜色,它的贡献是独立的.我们可以在一次点分治中合在一块处理(为什么时间复杂度是对的呢,因为我们每次改动只会根据当前点的颜色进行变动,而不是所有颜色对着它都来一遍).每次先对重心单独计算答案贡献,此时也将当前区域的各个答案贡献计算出来,并以此为基础(之后称之为基准贡献,即代码中的tot).对于每一棵子树,我们先df…

延迟调度的主要目的是提高数据本地性(data locality),减少数据在网络中的传输.对于那些输入数据不在本地的MapTask,调度器将会延迟调度他们,而把slot分配给那些具备本地性的MapTask. 延迟调度的大体思想如下: 若该job找到一个node-local的MapTask,则返回该task:若找不到,则延迟调度.即在nodeLocalityDelay时长内,重新找到一个node-local的MapTask并返回: 否则等待时长超过nodeLocalityDelay之后,寻找一个r…

Firt thought: an variation to LCS problem - but this one has many tricky detail. I learnt the solution from this link:https://github.com/wangyongliang/Algorithm/blob/master/hackerrank/Strings/Square%20Subsequences/main.cc And here is his code with my…

It is about how to choose btw. BFS and DFS. My init thought was to DFS - TLE\MLE. And its editorial gives a very neat BFS based idea which costs much less memory. https://www.hackerrank.com/challenges/beautiful-path/editorial…

It is marked as a NPC problem. However from the #1 code submission (https://www.hackerrank.com/CharlesOfria), it looks pretty much like a Brutal-Force (or simulation) based solution, mixed with some greedy strategies. To me the other NPC "Queens Revi…