B. Legacy 题目连接: http://codeforces.com/contest/786/problem/B Description Rick and his co-workers have made a new radioactive formula and a lot of bad guys are after them. So Rick wants to give his legacy to Morty before bad guys catch them. There are…

B. Legacy 题目连接: http://codeforces.com/contest/786/problem/B Description Rick and his co-workers have made a new radioactive formula and a lot of bad guys are after them. So Rick wants to give his legacy to Morty before bad guys catch them. There are…

D. Legacy time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Rick and his co-workers have made a new radioactive formula and a lot of bad guys are after them. So Rick wants to give his legacy…

D. Legacy time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Rick and his co-workers have made a new radioactive formula and a lot of bad guys are after them. So Rick wants to give his legacy…

Rick and his co-workers have made a new radioactive formula and a lot of bad guys are after them. So Rick wants to give his legacy to Morty before bad guys catch them. There are n planets in their universe numbered from 1 to n. Rick is in planet numb…

E. Editor The development of a text editor is a hard problem. You need to implement an extra module for brackets coloring in text. Your editor consists of a line with infinite length and cursor, which points to the current character. Please note that…

C. ReplacementTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/570/problem/C Description Daniel has a string s, consisting of lowercase English letters and period signs (characters '.'). Let's define the operation of replace…

题目链接:http://codeforces.com/contest/765/problem/F 题意概述: 给出一个序列,若干组询问,问给出下标区间中两数作差的最小绝对值. 分析: 这个题揭示着数据结构题目世界的真谛...... 在线显然凉凉......考虑离线做法. 本题的主要思想: 首先考虑把所有的询问按照右端点排序,用一个指针扫整个序列,同时考虑i作为一组差的右端可以对右端点大于等于i的询问做出的贡献.我们可以发现,我们扫到当前点i,对于所有询问的右端点大于等于i的询问,如果其左端点小于…

Strip time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Alexandra has a paper strip with n numbers on it. Let's call them ai from left to right. Now Alexandra wants to split it into some piec…

E. Pillars time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Marmot found a row with n pillars. The i-th pillar has the height of hi meters. Starting from one pillar i1, Marmot wants to jump…

D. Strip time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Alexandra has a paper strip with n numbers on it. Let's call them ai from left to right. Now Alexandra wants to split it into some p…

我会告诉你我看了很久很久才把题目看懂吗???怀疑智商了 原来他给的l,r还有k个数字都是下标... 比如给了一个样例 l, r, k, x1,x2,x3...xk,代表的是一个数组num[l]~num[r],其中有k个数num[x1],num[x2]....num[xk]这k个数都比l~r区间剩下的(下标不是x1...xk)的任何一个数大.题目就是给m个这种信息然后构造一个符合条件的数列 知道了这一点可以发现每一个信息都是一组偏序关系,即num[x1] > l~r区间剩下的数 .....num[…

A 一看到题,不是一道解不定方程的裸题吗,调了好久exgcd. 其实一个for就好了啊 B 一直WA ON TEST 7真是烦,一想会不会是编号太大了,又写了一个map版本,无用. 调了好久好久才发现有几次询问没有读完mmp C 调了一晚上,又看了数篇题解,终于看懂了QAQ 这是一道博弈论,借助图论/DP帮助完成. 博弈中有3种状态:必胜,必败,不一定 而我们需要将这些状态一直转移以求得结果. 如果A无论怎么移动,使B下一步必胜,则A的现在状态为必败.如果A可以移动任意一步,使B下一步必败,则A…

http://codeforces.com/contest/787/problem/D 题目大意:有n个点,三种有向边,这三种有向边一共加在一起有m个,然后起点是s,问,从s到所有点的最短路是多少? 第一种边:u->v w 表示节点u到v有连接一条有向边,权值为w 第二种边:u->[l,r] w  表示节点u到区间[l,r]连接一条有向边,权值为w 第三种边:[l,r]->u w  表示区间[l, r]所有的节点到u都有一条有向边,权值为w 思路: 我们知道,对于dijstra都是用pr…

B题打错调了半天,C题想出来来不及打,还好没有挂题 AC:AB Rank:96 Rating:2125+66->2191 A.Berzerk 题目大意:有一个东东在长度为n的环上(环上点编号0~n-1),两个玩家,玩家1有a种操作可选,玩家2有b种操作可选,每种操作可以让这个东东向前走若干步,两个玩家轮流操作,谁先让东东走到0谁胜,求出双方都选最优操作的情况下,东东开始在1~n-1各位置时玩家1先手和玩家2先手会必胜,必败还是无限循环.(a,b<n<=7000) 思路:类似DFS或者BF…

The Monster 签到题,算一下b+=a和d+=c,然后卡一下次数就可以了. Not Afraid 只要一组出现一对相反数就是安全的. Berzerk 题意:[1,n],两个人轮流走,谁能走到1谁就赢,求每个人先手在[2,n]时的胜负情况. 一直没怎么写过博弈论的题,但其实这种题也只是一个bfs. 必胜态:有一条边走到必败态 必败态:连出去的所有边都是必胜态. 方法:倒着bfs,把1作为必败态进队,如果当前是必败态,能到达都是必胜态,如果当前是必胜态,能到达的所有的点入度-1,如果入度减到…

来自FallDream的博客,未经允许,请勿转载,谢谢. ------------------------------------------------------- 大家好,我是一个假人.在学习OI的过程中,我凭借自己的努力,成功发明出了大顶的dij,并且帮助自己在cf和模拟赛上多过了 -2 道题.发明算法真美妙! -------------------------------------------------------- 不说了,D题因为dij打成大顶的挂了,血都吐出来了.A题瞎特判f…

F. SUM and REPLACE time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Let D(x) be the number of positive divisors of a positive integer x. For example, D(2) = 2 (2 is divisible by 1 and 2), D(6) …

Water Tree 给出一棵树,有三种操作: 1 x:把以x为子树的节点全部置为1 2 x:把x以及他的所有祖先全部置为0 3 x:询问节点x的值 分析: 昨晚看完题,马上想到直接树链剖分,在记录时间戳时需要记录一下出去时的时间戳,然后就是很裸很裸的树链剖分了. 稳稳的黄名节奏,因为一点私事所以没做导致延迟了 (ps:后来想了一下,不用树链剖分直接dfs序维护也行...) #include <set> #include <map> #include <list> #i…

Toposort   问题描述 给出nn个点mm条边的有向无环图. 要求删掉恰好kk条边使得字典序最小的拓扑序列尽可能小. 输入描述 输入包含多组数据. 第一行有一个整数TT, 表示测试数据组数. 对于每组数据: 第一行包含3个整数nn, mm和kk (1 \le n \le 100000, 0 \le k \le m \le 200000)(1≤n≤100000,0≤k≤m≤200000), 表示图中结点数目, 图中边的数目以及要删的边数. 接下来mm行, 每行包含两个整数u_iu​i​​ a…

分析:(官方题解) 首先考虑暴力,显然可以直接每次O(n^2) ​的连边,最后跑一次分层图最短路就行了. 然后我们考虑优化一下这个连边的过程 ,因为都是区间上的操作,所以能够很明显的想到利用线段树来维护整个图, 连边时候找到对应区间,把线段树的节点之间连边.这样可以大大缩减边的规模,然后再跑分层图最短路就可以了. 但是这样建图,每一次加边都要在O(logn)个线段树节点上加边,虽然跑的非常快,但是复杂度仍然是不科学的. 为了解决边的规模的问题,开两棵线段树,连边时候可以新建一个中间节点,在对应区…

题意: 思路: 线段树+Dijkstra(要堆优化的) 线段树要支持打标记 一个栅栏 拆成两个点 :左和右 新加一个栅栏的时候 看看左端点有没有被覆盖过 如果有的话 就分别从覆盖的那条线段的左右向当前的左端点连一条边权为距离的边 右端点同理 跑一遍Dijkstra 就好啦 复杂度:O(nlogn) //By SiriusRen #include <queue> #include <cstdio> #include <cstring> #include <algor…

http://codeforces.com/contest/787/problem/E 题目大意:给你n块,每个块都有一个颜色,定义一个k,表示在区间[l,r]中最多有k中不同的颜色.另k=1,2,3...n,问在每一种情况下,输出能划分出的最小的段落数. 例如: 51 3 4 3 3 ans = 4, 2, 1, 1, 1 [1], [3], [4], [3, 3] [1], [3, 4, 3, 3] [1, 3, 4, 3, 3] [1, 3, 4, 3, 3] [1, 3, 4, 3, 3…

A. Berzerk 题目连接: http://codeforces.com/contest/786/problem/A Description Rick and Morty are playing their own version of Berzerk (which has nothing in common with the famous Berzerk game). This game needs a huge space, so they play it with a computer…

http://codeforces.com/contest/787/problem/C 题目大意:有一个长度为n的环,第1个位置是黑洞,其他都是星球.已知在星球上(不含第一个黑洞)有一位神.有两个人,每个人有一个集合的数字,两人进行游戏,每人每轮可以让神从一个星球向后移动x位(x为目前两个人所拥有的集合中的一个任意数字,数字可以重复选).请求出神在2~n的每一个位置上时,两人分别先手的输赢情况,先手胜利输出WIN,先手必败输出LOOS,会无限循环输出LOOP. 思路:经典的有向图博弈(可惜我不会…

D. Water Tree time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Mad scientist Mike has constructed a rooted tree, which consists of n vertices. Each vertex is a reservoir which can be either…

有向图博弈问题. 能转移到一个必败态的就是必胜态. 能转移到的全是必胜态的就是必败态. 转移的时候可以用队列维护. 可以看这个 http://www.cnblogs.com/quintessence/p/6618640.html #include<cstdio> #include<queue> using namespace std; struct Node{ int who,pos; }; queue<Node>q; int n,len[2],to[2][7010],…

扩欧,a+bx=c+dx,输出x>=0且y>=0,且a+bx最小的解. 要注意不能只保证x非负,还得看看能否保证y也非负. #include<cstdio> #include<iostream> using namespace std; typedef long long ll; ll a,b,c,d; void exgcd(ll a,ll b,ll &d,ll &x,ll &y) { if(!b) { d=a; x=1; y=0; } else…

A. The Monster time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output A monster is chasing after Rick and Morty on another planet. They're so frightened that sometimes they scream. More accurately…

F. MEX Queries time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a set of integer numbers, initially it is empty. You should perform n queries. There are three different types…