CF833B The Bakery LG传送门 线段树优化DP. 其实这是很久以前就应该做了的一道题,由于颓废一直咕在那里,其实还是挺不错的一道题. 先考虑\(O(n^2k)\)做法:设\(f[i][j]\)表示\(1\)到\(i\)之间分割\(j\)次得到的最大值,\(g[i][j]\)表示\(i\)到\(j\)之间不同的颜色个数. 转移就是: \[f[i][j]=max \{f[t][j-1]+g[t+1][i] \} \qquad t \in [1,i)\] 但是时空都无法承受,考虑优化.…

  Some time ago Slastyona the Sweetmaid decided to open her own bakery! She bought required ingredients and a wonder-oven which can bake several types of cakes, and opened the bakery. Soon the expenses started to overcome the income, so Slastyona dec…

Description 将一个长度为n的序列分为k段 使得总价值最大一段区间的价值表示为区间内不同数字的个数 \(n\leq 35000,k\leq 50,1\leq a_i\leq n\) Solution 定义 \(dp[i][j]\) 表示前 i 个里面分 j 段的最大收益 一个显然的 dp 方程是 \(dp[i][j]=\max \limits_{1\leq p<i} dp[p][j-1]+w(p+1,i)\).复杂度 \(O(n^2k)\),GG. 考虑优化此方程,因为是取 max,容…

题目大意:给你一个序列(n<=35000),最多分不大于m块(m<=50),求每个块内不同元素的数量之和的最大值 考试的时候第一眼建图,没建出来,第二眼贪心 ,被自己hack掉了,又随手写了个dp方程,感觉可以用splay维护,发现有区间操作并可取,又发现这个方程只能用线段树维护,然后只剩40min了我没调完,而且线段树打错了...... 定义f[i][j]表示以第i个数为这个块的结尾,已经分了j块的答案的最大值 很明显,sum表示不同元素数量 对于每个元素,记录一个表示数 i 上一次出现的位…

标 * 的是推荐阅读的部分 / 做的题目. 1. 动态 DP(DDP)算法简介 动态动态规划. 以 P4719 为例讲一讲 ddp: 1.1. 树剖解法 如果没有修改操作,那么可以设计出 DP 方案 \(f_{i,0/1}\) 分别表示不选(\(0\))/ 选(\(1\))点 \(i\) 的最大权值,那么有 \(f_{i,0}=\sum_{x\in S_i}\max(f_{x,0},f_{x,1}),f_{i,1}=v_i+\sum_{x\in S_i}f_{i,0}\). 如果加上修改操作,那…

B. Bakery time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Masha wants to open her own bakery and bake muffins in one of the n cities numbered from 1 to n. There are m bidirectional roads,…

Bakery 题目链接: http://codeforces.com/contest/707/problem/B Description Masha wants to open her own bakery and bake muffins in one of the n cities numbered from 1 to n. There are m bidirectional roads, each of whose connects some pair of cities. To bake…

面包店烹制面包及蛋糕,由n个销售员卖出.当有顾客进店购买面包或蛋糕时,应先在取号机上取号,然后等待叫号,若有销售员空闲时便叫下一号,试用信号量和PV操作写出Bakery算法的同步程序. 设计要求 1)为每个销售员/顾客产生一个进程/线程,设计正确的同步算法: 2)每个顾客进入面包店后,即时显示"Entered",还同时显示共有几名顾客: 3)至少有个顾客: 4)多个销售员/顾客程序须共享操作函数代码. 专业程序代写c++程序代写…

D. The Bakery time limit per test:2.5 seconds memory limit per test:256 megabytes input:standard input output:standard output Some time ago Slastyona the Sweetmaid decided to open her own bakery! She bought required ingredients and a wonder-oven whic…

Some time ago Slastyona the Sweetmaid decided to open her own bakery! She bought required ingredients and a wonder-oven which can bake several types of cakes, and opened the bakery. Soon the expenses started to overcome the income, so Slastyona decid…