原文链接https://www.cnblogs.com/zhouzhendong/p/CF264C.html 题目传送门 - CF264C 题意 给定一个有 $n$ 个元素的序列,序列的每一个元素是个球,第 $i$ 个球具有 $v_i$ 的值,颜色为 $c_i$ . 一个序列的价值为每一个球价值和. 在一个序列中,第 $i$ 个球的价值为: 当 $c_i=c_{i-1}(i>1)$ 时,$value=a\times v_i$. 否则, $value=b\times v_i$ . 接下来有 $q$…

作者:jostree 转载请注明出处 http://www.cnblogs.com/jostree/p/4098409.html 题目链接:poj 3783 Balls 动态规划 100层楼投鸡蛋问题 使用动态规划算法,使用$dp[i][j]$表示对于i层楼并拥有$j$个鸡蛋时能够判断鸡蛋质量需要的最少次数.假如我们在第$k$层扔下一个鸡蛋,则有两种情况,如果鸡蛋没有损坏则问题相当于我们对于$i-k$层楼拥有$j$个鸡蛋所需的最少的次数.如果鸡蛋损坏了,则问题相当于对于k层楼拥有$j-1$个鸡蛋…

There are n cities and n - 1 roads in the Seven Kingdoms, each road connects two cities and we can reach any city from any other by the roads. Theon and Yara Greyjoy are on a horse in the first city, they are starting traveling through the roads. But…

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…

Let's call the roundness of the number the number of zeros to which it ends. You have an array of n numbers. You need to choose a subset of exactly k numbers so that the roundness of the product of the selected numbers will be maximum possible. Input…

题目链接:http://codeforces.com/contest/219/problem/D 树dp //#pragma comment(linker, "/STACK:102400000, 102400000") #include <algorithm> #include <iostream> #include <cstdlib> #include <cstring> #include <cstdio> #include…

http://codeforces.com/problemset/problem/219/D 题目大意: 给出一棵树,但是它的边是有向边,选择一个城市,问最少调整多少条边的方向能使一个选中城市可以到达所有的点,输出最小的调整的边数,和对应的点. 思路:先预处理一个点为根的代价,然后去dfs移动,总复杂度是O(n) #include<cstdio> #include<cmath> #include<algorithm> #include<cstring> #i…

Choosing Capital for Treeland time limit per test 3 seconds memory limit per test 256 megabytes input standard input output standard output The country Treeland consists of n cities, some pairs of them are connected with unidirectional roads. Overall…

题目链接:http://codeforces.com/contest/219/problem/D 题目大意: 给定一个n个节点的数和连接n个节点的n - 1条有向边,现在要选定一个节点作为起始节点,从这个点出发需要能走到其余每个节点,途中必然要调整有向边的方向,请求出当选定哪些节点作为初始节点时,所要调整的有向边最少,输出最小调整的边数和这些节点. 分析: Hint:城市结构是树型结构. 代码如下: #include <bits/stdc++.h> using namespace std; #…

原文链接http://www.cnblogs.com/zhouzhendong/p/8848990.html 题目传送门 - CodeForces 623E 题意 给定$n,k$. 让你构造序列$a(0<a_i<2^k)$,满足$b_i(b_i=a_1\ or\ a_2\ or\ \cdots\ or\ a_i)$严格单调递增.($or$为按位或) 问你方案总数.对$10^9+7$取模. $n\leq 10^{18},k\leq 30000$ 题解 毛爷爷论文题. 我怀疑我看到的是假论文.里面…