sky123博客

题目链接You are given three non-negative integers aaa, bbb, and ccc. Find three positive integers xxx, yyy, and zzz that satisfy x mod y=ax\bmod y=axmody=a, y mod z=by\bmod z=bymodz=b, and z mod x=cz\bmod x=czmodx=c.InputThe first line contains an integer t

Little A has an array a of length nnn , which is indexed from 111 to nnn. A total of nnn numbers are stored in a1,a2,⋯,ana_1 ,a_2,⋯,a_na1​,a2​,⋯,an​ , and little A wants to sort them in non-decreasing order.Little A can perform several rounds of operation

题目链接Omkar and Akmar are playing a game on a circular board with nnn (2≤n≤1062 \leq n \leq 10^62≤n≤106) cells. The cells are numbered from 111 to nnn so that for each iii (1≤i≤n−11 \leq i \leq n-11≤i≤n−1) cell iii is adjacent to cell i+1i+1i+1 and cell 111

题目链接You are given a tree with nnn nodes. As a reminder, a tree is a connected undirected graph without cycles.Let a1,a2,…,ana_1, a_2, \ldots, a_na1​,a2​,…,an​ be a sequence of integers. Perform the following operation exactly nnn times:Select an uneras

题目链接Cirno has prepared nnn arrays of length nnn each. Each array is a permutation of nnn integers from 111 to nnn. These arrays are special: for all 1≤i≤n1 \leq i \leq n1≤i≤n, if we take the iii-th element of each array and form another array of length nn

题目链接题目描述The boundary of the table is a circle. n{n}n chairs are at n{n}n points on the circle whose convex hull is a regular polygon with n{n}n vertices. We name the points 0,…,n−10,\ldots, n-10,…,n−1 in counterclockwise order. The i{i}i-th bowl is at po

题目链接题目描述Consider a grid pattern with n{n}n rows and {m}m columns. There are (n+1)×(m+1)(n+1)\times(m+1)(n+1)×(m+1) grid points in total which is the intersections of n+1{n+1}n+1 horizontal lines and m+1{m+1}m+1 vertical lines. We number the horizontal li

题目链接Formally, the vertices in a rooted tree will be marked black or white, and if a vertex is marked black, all the vertices in its subtree should also be marked black. Given a rooted tree, it’s easy to calculate the number of possible valid ways to mark

题目链接Megumi公司的晚会上，有一个节目正在彩排。在一个巨大的二维舞台上，有 nnn 个演员，编号为 1−n1-n1−n 和一根无限长的棍子。为了监视彩排，任意三位演员不在同一条直线上，而且棍子上画了一个单向箭头。这个节目的要求是：选定某一位演员x，并确定棍子箭头的指向，让这位演员拿着棍子，使得除他之外没有其他演员接触棍子。然后表演开始。表演进行时，拿着棍子的演员a会顺时针旋转，当棍子碰到另外一位演员b时，演员b会接过棍子并继续旋转。为了节目效果，导演艾洛想找某一位特定的演员和在棍子

题目链接题目描述小F最近在研究蜂巢，如下图所示，这是一个蜂巢的横剖图，每一个格子都是一个正六边形，多个格子平铺构成一个无限大的平面。我们以中央的格子作为原点，按照下图规律，一圈一圈向外将每个格子都编上号。小F想知道，如果一个蜜蜂当前在编号为x的格子处，它想到达编号为y的格子，最优情况下它最少需要经过多少个格子（包含起点终点）。蜜蜂在蜂巢里只能爬行，也就是说它每次只能爬到相邻的格子里。你需要支持多组询问。输入描述:第一行，一个整数 T (1≤T≤100000)T\ (1 \leq T

题目链接题目描述As a master of parallel computing, schwer is recently considering about the method to achieve quick sorting on parallel computers. He needs your help!Given a permutation (p1,⋯ ,pn)(p_1,\cdots,p_n)(p1​,⋯,pn​) , you need to sort the permutation wi

题目链接You are given a matrix n×mn \times mn×m, initially filled with zeroes. We define ai,ja_{i, j}ai,j​ as the element in the iii-th row and the jjj-th column of the matrix.Two cells of the matrix are connected if they share a side, and the elements in th

题目链接Let f(x)f(x)f(x) be the sum of digits of a decimal number xxx.Find the smallest non-negative integer xxx such that f(x)+f(x+1)+⋯+f(x+k)=nf(x) + f(x + 1) + \dots + f(x + k) = nf(x)+f(x+1)+⋯+f(x+k)=n.InputThe first line contains one integer ttt (1≤t≤

题目链接Monocarp would like to open a bakery in his local area. But, at first, he should figure out whether he can compete with other shops.Monocarp plans that the bakery will work for nnn days. On the iii-th day, aia_iai​ loaves of bread will be baked in th

题目链接Nezzar loves the game osu!.osu! is played on beatmaps, which can be seen as an array consisting of distinct points on a plane. A beatmap is called nice if for any three consecutive points A,B,CA,B,CA,B,C listed in order, the angle between these three

题目链接Lunar rover finally reached planet X. After landing, he met an obstacle, that contains permutation ppp of length nnn. Scientists found out, that to overcome an obstacle, the robot should make ppp an identity permutation (make pi=ip_i = ipi​=i for all

题目链接During cleaning the coast, Alice found nnn piles of stones. The iii-th pile has aia_iai​ stones.Piles iii and i+1i + 1i+1 are neighbouring for all 1≤i≤n−11 \leq i \leq n - 11≤i≤n−1. If pile iii becomes empty, piles i−1i - 1i−1 and i+1i + 1i+1 doesn’t

Let’s call two strings aaa and bbb (both of length kkk) a bit similar if they have the same character in some position, i. e. there exists at least one i∈[1,k]i \in [1, k]i∈[1,k] such that ai=bia_i = b_iai​=bi​.You are given a binary string sss of length

题目链接题目描述MianKing has a Graph Constructer : The input of it is a sequence a1...n (0≤ai<260)a_{1...n}~(0\leq a_i<2^{60})a1...n​ (0≤ai​<260) and the output of it is an undirected graph with nnn nodes, edge (x,y)(x,y)(x,y) is in this graph

题目链接题目描述Bobo has two sequences a1,a2,…,ana_1, a_2, \ldots, a_na1​,a2​,…,an​ and b1,b2,…,bnb_1, b_2, \ldots, b_nb1​,b2​,…,bn​. He would like to perform the following operations:1 x y\text{1 }x\ y1 x y, change the value of axa_xax​ to

题目链接Problem StatementWe have a directed graph with NNN vertices numbered 111 to NNN. NNN strings of length NNN each, S1,S2,…,SNS_1,S_2,\ldots,S_NS1​,S2​,…,SN​, represent the edges in the graph. Specifically, Si,jS_{i,j}Si,j​ is 1 if there is an edge from

题目链接Little Rabbit walks into a shopping mall and comes across a lottery activity. There are nnn boxes. Inside the iii-th box, there are xix_ixi​ balls labeled with 2ai2^{a_i}2ai​. Little Rabbit can pick out any number (including zero) of balls from each b

题目链接You are given a sequence of nnn integers a1,a2,…,ana_1, a_2, \ldots, a_na1​,a2​,…,an​.You have to construct two sequences of integers bbb and ccc with length nnn that satisfy:for every iii (1≤i≤n1\leq i\leq n1≤i≤n) bi+ci=aib_i+c_i=a_ibi​+ci​=ai​bb

On the competitive programming platform CodeCook, every person has a rating graph described by an array of integers aaa of length nnn. You are now updating the infrastructure, so you’ve created a program to compress these graphs. The program works as follo

题目链接We start with a permutation a1,a2,…,ana_1,a_2,…,a_na1​,a2​,…,an​ and with an empty array bbb. We apply the following operation kkk times.On the iii-th iteration, we select an index tit_iti​ (1≤ti≤n−i+1)(1≤t_i≤n−i+1)(1≤ti​≤n−i+1), remove ati from the

题目链接Let there be a simple graph with NNN vertices but we just know the degree of each vertex. Is it possible to reconstruct the graph only by these information?A simple graph is an undirected graph that has no loops (edges connected at both ends to the s

题目链接Bob is an active user of the social network Faithbug. On this network, people are able to engage in a mutual friendship. That is, if aaa is a friend of bbb, then bbb is also a friend of aaa. Each user thus has a non-negative amount of friends.This mo

Problem DescriptionFor a given permutation a1,a2,…,ana_1,a_2,\dots,a_na1​,a2​,…,an​ of length nnn, we defined the neighbor sequence bbb of aaa, the length of which is n−1n−1n−1, as following:bi={0 ai<ai+11 ai>ai+1b_i=\left\{\begin{matrix

题目链接Problem DescriptionA mine-sweeper map can be expressed as an r×cr×cr×c grid, and each cell of the grid is either mine cell or non-mine cell. A mine cell has no number on it, while a non-mine cell has a number, the number of mine cells that share at l

题目链接对于整数序列 (a1,a2,⋯ ,an)(a_1,a_2,\cdots,a_n)(a1​,a2​,⋯,an​) 和 1∼n1\sim n1∼n 的排列 (p1,p2,⋯ ,pn)(p_1,p_2,\cdots,p_n)(p1​,p2​,⋯,pn​)，称 (a1,a2,⋯ ,an)(a_1,a_2,\cdots,a_n)(a1​,a2​,⋯,an​) 符合 (p1,p2,⋯ ,pn)(p_1,p_2,\cdots,p_n)(p1​,p2​,⋯,pn​)，当且仅当：{a}\{a\}{a} 中任意

题目链接Problem StatementThere is a grid of squares with H+1H+1H+1 horizontal rows and WWW vertical columns.You will start at one of the squares in the top row and repeat moving one square right or down. However, for each integer iii from 111 through HHH, y

Problem DescriptionOne day when Little Q woke up, he found himself being inside a 2D pixel world. The world is a grid with n×mn×mn×m square cells. Little Q can only walk along the side of these cells, which means he can stay at a point (x,y)(x,y)(x,y) if

题目链接You are given an array a of length 2n2^n2n. You should process qqq queries on it. Each query has one of the following 444 types:Replace(x,k)Replace(x,k)Replace(x,k) — change axa_xax​ to kkk;Reverse(k)Reverse(k)Reverse(k) — reverse each subarray

Boboniu defines BN-string as a string s of characters ‘B’ and ‘N’.You can perform the following operations on the BN-string s:Remove a character of s.Remove a substring “BN” or “NB” of s.Add a character ‘B’ or ‘N’ to the end of s.Add a string “BN” or

Boboniu has a directed graph with nnn vertices and mmm edges.The out-degree of each vertex is at most kkk.Each edge has an integer weight between 111 and mmm. No two edges have equal weights.Boboniu likes to walk on the graph with some specific rules, w

There is an undirected tree of nnn vertices, connected by n−1n−1n−1 bidirectional edges. There is also a snake stuck inside of this tree. Its head is at vertex aaa and its tail is at vertex bbb. The snake’s body occupies all vertices on the unique simple p

Carousel Boutique is busy again! Rarity has decided to visit the pony ball and she surely needs a new dress, because going out in the same dress several times is a sign of bad manners. First of all, she needs a dress pattern, which she is going to cut out

You are given nnn segments [l1,r1],[l2,r2],…,[ln,rn][l_1,r_1],[l_2,r_2],…,[l_n,r_n][l1​,r1​],[l2​,r2​],…,[ln​,rn​]. Each segment has one of two colors: the iii-th segment’s color is tit_iti​.Let’s call a pair of segments iii and jjj bad if the following t

You have a simple and connected undirected graph consisting of nnn nodes and mmm edges.Consider any way to pair some subset of these nnn nodes such that no node is present in more than one pair.This pairing is valid if for every pair of pairs, the induce

链接：https://ac.nowcoder.com/acm/contest/5672/A来源：牛客网题目描述Nowadays, the Kingdom of Dreamgrid is suffering from a national pandemic. Fortunately, president Baobao is working effectively with the Center for Disease Control (CDC) and they are trying their bes