D. Secret Passwords One unknown hacker wants to get the admin's password of AtForces testing system, to get problems from the next contest. To achieve that, he sneaked into the administrator's office and stole a piece of paper with a list of n passwo…

链接: https://codeforces.com/contest/1263/problem/D 题意: One unknown hacker wants to get the admin's password of AtForces testing system, to get problems from the next contest. To achieve that, he sneaked into the administrator's office and stole a piec…

B. Balls Game Time Limit: 1 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/430/problem/B Description Iahub is training for the IOI. What is a better way to train than playing a Zuma-like game? There are n balls put in a row. Each ball i…

E. Clockwork Bomb 题目连接: http://www.codeforces.com/contest/650/problem/E Description My name is James diGriz, I'm the most clever robber and treasure hunter in the whole galaxy. There are books written about my adventures and songs about my operations…

E. Table Compression 题目连接: http://www.codeforces.com/contest/651/problem/E Description Little Petya is now fond of data compression algorithms. He has already studied gz, bz, zip algorithms and many others. Inspired by the new knowledge, Petya is now…

题意:给你n个点,m条边,然后让你使得这个这个图成为一个协和图,需要加几条边.协和图就是,如果两个点之间有一条边,那么左端点与这之间任意一个点之间都要有条边. 思路:通过并查集不断维护连通量的最大编号的节点,然后遍历即可. 代码: #include<bits/stdc++.h> using namespace std; #define int long long #define N 1005000 int f[N];int n,m; int getf(int v){// 并查集模板 if(v=…

E. Table Compression time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Little Petya is now fond of data compression algorithms. He has already studied gz, bz, zipalgorithms and many others.…

题意:对于一张图,如果$a$与$b$连通,则对于任意的$c(a<c<b)$都有$a$与$c$连通,则称该图为和谐图,现在给你一张图,问你最少添加多少条边使图变为和谐图. 思路:将一个连通块内最大的点做为根,用并查集维护,遍历一遍,对于某个点$i$及该点连通块内的根$fx$,$i$到$fx$内的每一个点,当与$i$不属于一个集合时,进行合并,答案加一,同时更新该连通块的根. #include <iostream> #include <algorithm> #include…

Little Petya is now fond of data compression algorithms. He has already studied gz, bz, zip algorithms and many others. Inspired by the new knowledge, Petya is now developing the new compression algorithm which he wants to name dis. Petya decided to…

题意:给你带边权的树,有\(m\)次询问,每次询问有多少点对\((u,v)\)之间简单路径上的最大边权不超过\(q_i\). 题解:真的想不到用最小生成树来写啊.... 我们对边权排序,然后再对询问的\(q_i\)排序,我们可以枚举\(q_i\),然后从last开始遍历边权,如果边权不大于\(q_i\),那么就可以用并查集将两个连通块合并且计数(因为我们是从小到大枚举的,所以将它们合并并不会对后面有影响,反而还会方便我们计数),\(cnt\)表示连通块的节点数,合并时贡献为\(res=cnt[f…

题目传送门 /* 构造+暴力:按照题目意思,只要10次加1就变回原来的数字,暴力枚举所有数字,string大法好! */ /************************************************ Author :Running_Time Created Time :2015-8-3 8:43:02 File Name :A.cpp *************************************************/ #include <cstdio>…

Codeforces Round #603 (Div. 2) A. Sweet Problem A. Sweet Problem time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You have three piles of candies: red, green and blue candies: the first pile…

A. Sweet Problem (找规律) 题目链接 大致思路: 有一点瞎猜的,首先排一个序, \(a_1>a_2>a_3\) ,发现如果 \(a_1>=a_2+a_3\) ,那么答案肯定是 \(a_2+a_3\) ,然后发现发现规律当 \(a_2==a_3\) 的时候,还可以贡献 \((a_1+a_2+a_3)/2\) 的答案,所以只要 \(a_1\) 和 \(a_2\) 减掉一个值就可以了. B. PIN Codes (暴力) 题目链接 大致思路: 可以知道,存在一个数字不同的pi…

传送门 感觉脑子还是转得太慢了QAQ,一些问题老是想得很慢... A. Sweet Problem 签到. Code /* * Author: heyuhhh * Created Time: 2019/11/29 22:36:19 */ #include <iostream> #include <algorithm> #include <vector> #include <cmath> #include <set> #include <ma…

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…

链接: https://codeforces.com/contest/1263/problem/E 题意: 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 point…

题目链接:https://codeforces.com/contest/1263/problem/D 题意:有n个小写字符串代表n个密码,加入存在两个密码有共同的字母,那么说这两个密码可以认为是同一个集合,可以互相破解,先求有多少个不同集合的密码 思路:简单的并查集.首先一共有26个字母,对于每个密码,我们合并其所涵盖的字母,例如密码1:abcd,那么abcd合并起来,含有abcd的任意密码都同属于一个集合,所有我们把n个密码串先做一次合并.最终再扫一遍所有的密码串,用set维护集合的个数,最终…

C. The Labyrinth 题目连接: http://www.codeforces.com/contest/616/problem/C Description You are given a rectangular field of n × m cells. Each cell is either empty or impassable (contains an obstacle). Empty cells are marked with '.', impassable cells are…

题目链接:http://codeforces.com/contest/691/problem/D 题意: 题目给出一段序列,和m条关系,你可以无限次互相交换这m条关系 ,问这条序列字典序最大可以为多少 思路: 并查集维护这m条关系,用个vector存一下当前点所能到达的点,拍下序大的优先,输出的时候输出当前点所能找到的最大的数,已输出的标记下就好了. 实现代码: #include<bits/stdc++.h> using namespace std; ; int f[M],vis[M],a[M…

B. Secret Combination time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You got a box with a combination lock. The lock has a display showing n digits. There are two buttons on the box, each…

链接: https://codeforces.com/contest/1263/problem/C 题意: On the well-known testing system MathForces, a draw of n rating units is arranged. The rating will be distributed according to the following algorithm: if k participants take part in this event, t…

链接: https://codeforces.com/contest/1263/problem/B 题意: A PIN code is a string that consists of exactly 4 digits. Examples of possible PIN codes: 7013, 0000 and 0990. Please note that the PIN code can begin with any digit, even with 0. Polycarp has n (…

链接: https://codeforces.com/contest/1263/problem/A 题意: You have three piles of candies: red, green and blue candies: the first pile contains only red candies and there are r candies in it, the second pile contains only green candies and there are g ca…

F. Economic Difficulties 题目链接: https://codeforces.com/contest/1263/problem/F 题目大意: 两棵树,都有n个叶子节点,一棵树正着放,一棵树倒着放,叶子节点从左到右对应装置1,2,3,4...n,问最多能删掉多少条边,使得装置能与两棵树任意一个根节点1相连. 解题思路: mp[ i ][ j ]是装置 i 到 j 这段区间删除这段连续区间所能删除的最大边数,两个图分开看,算出每一个图中如果不连通这段区间对应的叶子节点所能删除…

E. Editor 题目链接: https://codeforces.com/contest/1263/problem/E 题目大意: 输入一个字符串S1含有‘(’ , ‘)’ , ‘R’ , ‘L’ 以及其他字符.根据这个字符串,得到相应的字符串S2.起始idx=1即S2的初始坐标,然后从左到右读取S1,当遇到'L',idx减小1(当无法左移的情况下idx不减小),当遇到'R',idx增加1,当读取到其他字符时,将idx这个位置上的字符更新为读取到的新的字符.然后输出每一步得到的字符串S2最大…

http://codeforces.com/contest/1263/problem/E 题意:求合法的括号序列 #include<bits/stdc++.h> using namespace std; typedef long long ll; #define lson root<<1,l,midd #define rson root<<1|1,midd+1,r #define pb push_back const int inf=0x3f3f3f3f; const…

F. Economic Difficulties An electrical grid in Berland palaces consists of 2 grids: main and reserve. Wires in palaces are made of expensive material, so selling some of them would be a good idea! Each grid (main and reserve) has a head node (its num…

C. Everyone is a Winner! On the well-known testing system MathForces, a draw of n rating units is arranged. The rating will be distributed according to the following algorithm: if k participants take part in this event, then the n rating is evenly di…

B. PIN Codes A PIN code is a string that consists of exactly 4 digits. Examples of possible PIN codes: 7013, 0000 and 0990. Please note that the PIN code can begin with any digit, even with 0. Polycarp has n (2≤n≤10) bank cards, the PIN code of the i…

A. Sweet Problem the first pile contains only red candies and there are r candies in it, the second pile contains only green candies and there are g candies in it, the third pile contains only blue candies and there are b candies in it. Each day Tany…