Long long ago, there is a sequence A with length n. All numbers in this sequence is no smaller than 1 and no bigger than n, and all numbers are different in this sequence. Please calculate how many quad (a,b,c,d) satisfy: 1. 1≤a<b<c<d≤n1≤a<b&l…

Mr. Frog has an integer sequence of length n, which can be denoted as a1,a2,⋯,ana1,a2,⋯,anThere are m queries. In the i-th query, you are given two integers lili and riri. Consider the subsequence ali,ali+1,ali+2,⋯,ariali,ali+1,ali+2,⋯,ari. We can de…

Sequence II Time Limit: 5000/2500 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Problem Description Long long ago, there is a sequence A with length n. All numbers in this sequence is no smaller than 1 and no bigger than n, and all nu…

题目链接 Sequence II Time Limit: 5000/2500 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 331    Accepted Submission(s): 151 Problem Description Long long ago, there is a sequence A with length n. All numbers in this se…

Sequence IITime Limit: 5000/2500 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Problem DescriptionLong long ago, there is a sequence A with length n. All numbers in this sequence is no smaller than 1 and no bigger than n, and all numbers…

Sequence II Time Limit: 9000/4500 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 1422    Accepted Submission(s): 362 Problem Description Mr. Frog has an integer sequence of length n, which can be denoted as a1,a2…

Sequence II Problem Description   Mr. Frog has an integer sequence of length n, which can be denoted as a1,a2,⋯,an There are m queries. In the i-th query, you are given two integers li and ri. Consider the subsequence ali,ali+1,ali+2,⋯,ari. We can de…

树阵: 每个号码的前面维修比其数数少,和大量的这后一种数比他的数字 再枚举每一个位置组合一下 Sequence II Time Limit: 5000/2500 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 121    Accepted Submission(s): 58 Problem Description Long long ago, there is a sequen…

Sequence II Time Limit: 5000/2500 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 652    Accepted Submission(s): 164 Problem Description Long long ago, there is a sequence A with length n. All numbers in this sequenc…

6990: Sequence II 时间限制: 3 Sec  内存限制: 128 MB提交: 206  解决: 23[提交][状态][讨论版][命题人:admin] 题目描述 We define an element ai in a sequence "good", if and only if there exists a j(1≤ j < i) such that aj < ai.Given a permutation p of integers from 1 to n…

[HDU5919]Sequence II 试题描述 Mr. Frog has an integer sequence of length n, which can be denoted as a1,a2,⋯,an There are m queries. In the i-th query, you are given two integers li and ri. Consider the subsequence al_i,al_(i+1),al_(i+2),⋯,ari. We can den…

http://acm.hdu.edu.cn/showproblem.php?pid=5147 题意:问有多少个这样的四元组(a,b,c,d),满足条件是 1<=a<b<c<d; Aa<Ab; Ac<Ad; 思路:用树状数组求,从右向左求在这个数之前形成多少个逆序数对记录在r数组里面,然后在从左向右求出在输入这个数之前形成多少个逆序数对存在l数组里面,然后枚举b就行: #include <cstdio> #include <cstring> #in…

题意: 给一串数字,每个数字的位置是这个数第一次出现的位置. 每个询问对于序列的一个子区间,设一共有k个不同的数,求第ceil(k/2)个数的位置. 因为强制在线,所以离线乱搞pass掉. 主席树可解. 考虑一个数列: p      1 2 3 4 5 6  // 原序列标号 a : 1 2 1 2 3 4  // 原序列 p1 1 2 1 2 5 6  // 子序列开始下标为1 p2        2 3 1 5 6 p3           3 4 5 6 p4              4…

[题目链接]http://acm.hdu.edu.cn/showproblem.php?pid=5919 [题目大意] 给出一个数列,每次查询数列中,区间非重元素的下标的中位数.查询操作强制在线. [题解] 因为查询的是下标,因此,我们直接在下标操作表示这里有没有数字,然后查询k大数即可,非重元素即需要在区间每个数第一次出现的地方+1,然后对处理完的区间进行查询即可,考虑到查询强制在线,不能扫描线,因此只能建立可持久化线段树,线段树的第i个版本表示第i个位置往后的每个元素第一次出现的位置,那么查…

链接:http://acm.hdu.edu.cn/showproblem.php?pid=5919 大致题意: 给你一个长度为n的序列,q个询问,每次询问是给你两个数x,y,经过与上一次的答案进行运算会得到一个区间[x,y],假设这个区间内有k个数,对k个数第一次出现的位置进行排序取第(k+1)/2个数. 思路: 看题意可知要求的是区间不同数的个数和区间第k小,强制在线, 之前正好写过求区间不同数的个数的三种解法:离线树状数组,主席树,莫队,因为这道题是强制在线,莫队和离线树状数组都不能用,这里…

http://acm.split.hdu.edu.cn/showproblem.php?pid=5919 题意:给出一串序列,每次给出区间,求出该区间内不同数的个数k和第一个数出现的位置(将这些位置组成一个新的序列),输出这里面的第ceil(k/2)个数. 思路: 因为每个区间只需要统计第一个数出现的位置,那么从右往左来建树,如果该数没有出现,那么就将该位置+1,否则要将上一次出现的位置-1后再在该位置+1. 统计不同数的个数很简单,就是线段树查询. 查询出第k小的数也很简单,因为我们是从后往前…

HDU 5919 题意: 动态处理一个序列的区间问题,对于一个给定序列,每次输入区间的左端点和右端点,输出这个区间中:每个数字第一次出现的位子留下, 输出这些位子中最中间的那个,就是(len+1)/2那个. 思路: 主席树操作,这里的思路是从n到1开始建树.其他就是主席树查询区间第K小,计算区间不同值个数. #include <algorithm> #include <iterator> #include <iostream> #include <cstring&…

题意:有A1 ~ An组成的数组,给你l r,L = min((l + ans[i - 1]) % n + 1, (r + ans[i - 1]) % n + 1),R = max((l + ans[i - 1]) % n + 1, (r + ans[i - 1]) % n + 1),你先需要的到L,R区间有k个不同的数字,然后问你L,R区间第(k + 1)/ 2个不同的数字下标是多少? 思路:显然是个在线询问. 我们之前已经会用主席树求区间内有多少不同数字了:从左到右把每个数字的位置存进每个操…

题意: 给定长度为n的序列和q次询问.每次询问给出一个区间(L,R),求出区间内每个数第一次出现位置的中位数,强制在线. 题解: 用主席树从右向左的插入点.对于当前点i,如果a[i]出现过,则把原位置-1,i处+1.这样保证了每个点只出现1次. 对于询问区间(L,R),求出L节点[L,R]的值即为区间内有多少不同的数.最后就是主席树求k_th的操作.倒着插省去了二分的复杂度. #include <iostream> #include <cstdio> #include <al…

链接: http://acm.hdu.edu.cn/showproblem.php?pid=1027 Ignatius and the Princess II Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 5822    Accepted Submission(s): 3433 Problem Description Now our h…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1005 Number Sequence Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 85249    Accepted Submission(s): 20209 Problem Description A number sequence…

Problem Description A number sequence is defined as follows: f(1) = 1, f(2) = 1, f(n) = (A * f(n - 1) + B * f(n - 2)) mod 7. Given A, B, and n, you are to calculate the value of f(n).   Input The input consists of multiple test cases. Each test case…

http://acm.hdu.edu.cn/showproblem.php?pid=4513 吉哥系列故事——完美队形II Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 65535/32768 K (Java/Others)Total Submission(s): 1544    Accepted Submission(s): 577 Problem Description 吉哥又想出了一个新的完美队形游戏! 假设有n个人按顺序站…

Problem Description Chiaki is interested in an infinite sequence a1,a2,a3,..., which is defined as follows: an={1an−an−1+an−1−an−2n=1,2n≥3 Chiaki would like to know the sum of the first n terms of the sequence, i.e. ∑i=1nai. As this number may be ver…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5064 题目意思:给出n个数:a1, a2, ..., an,然后需要从中找出一个最长的序列 b1, b2, ...,  bt.需要满足两个条件(1)b1≤b2≤…≤bt   (2)b2−b1≤b3−b2≤⋯≤bt−bt−1.求出最大的 t 为多少. 遗留大半年的题目呀呀呀呀~~~~!!!首先非常感谢乌冬子大半年前的指点迷津,呕心沥血想了大半天举出个反例,以便指出我算法的错误.为了纪念这个伟大的人物(…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5087 题目意思:找出第二个最长递增子序列,输出长度.就是说,假如序列为 1 1 2,第二长递增子序列是1 2(下标为2 3),而第一长递增子序列也是(下标为 1 3). 我一开始天真的以为,还是利用求最长递增子序列的算法啦,第二长不就是对dp 数组sort完后(从小到大)的dp[cnt-1] 啦,接着就呵呵啦----= = 题解说,要加多一个 dp 数组,以便对当前下标值为 i 的数 a[i] 为结…

Number Sequence Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 24116    Accepted Submission(s): 10232 Problem Description Given two sequences of numbers : a[1], a[2], ...... , a[N], and b[1],…

Given a binary tree, you need to find the length of Longest Consecutive Path in Binary Tree. Especially, this path can be either increasing or decreasing. For example, [1,2,3,4] and [4,3,2,1] are both considered valid, but the path [1,2,4,3] is not v…

链接: http://acm.hdu.edu.cn/showproblem.php?pid=2236 代码: #include<cstdio> #include<cstring> #include<cmath> #include<iostream> #include<algorithm> using namespace std; #define N 105 #define INF 0xffffff ///匹配 ///只需要用二分找一个区间, //…

http://poj.org/problem?id=2478 http://acm.hdu.edu.cn/showproblem.php?pid=2824 欧拉函数模板裸题,有两种方法求出所有的欧拉函数,一是筛法,而是白书上的筛法. 首先看欧拉函数的性质: 欧拉函数是求小于n且和n互质(包括1)的正整数的个数.记为φ(n). 欧拉定理:若a与n互质,那么有a^φ(n) ≡ 1(mod n),经常用于求乘法逆元. 若p是一个质数,那么φ(p) = p-1,注意φ(1) = 1. 欧拉函数是积性函数…