传送门 解题思路 贪心.对于一段区间中,可以将这段区间中相同的元素同时变成\(c\),但要付出的代价是区间中等于\(c\)的数的个数,设\(sum[i]\)表示等于\(c\)数字的前缀和,Max[i]表示数字\(i\)的最大个数.那么只要\(O(n)\)的扫一遍,维护一下每个数字的\(max\),具体做法是看一下\(Max[a[i]]\)大还是\(sum[i]\)大,如果\(sum\)大的话,说明前面都不变,直接把\(Max\)赋值成\(sum[i]+1\),否则直接让\(Max[i]++\),…

E. Increasing Frequency 题目链接:https://codeforces.com/contest/1082/problem/E 题意: 给出n个数以及一个c,现在可以对一个区间上的数同时加上或减去一个值,问最后c的最多数量为多少. 题解: 这题挺有意思的,我们通过分析题目可以发现,对于每一个d,如果把[l,r]里面的d都变为c,则最后c的数量为cnt(c,1,l-1)+cnt(c,r+1,n)+cnt(d,l,r). 这个式子变化一下,有:cnt(c,1,n)+cnt(d,…

You are given array a a of length n n . You can choose one segment [l,r] [l,r] (1≤l≤r≤n 1≤l≤r≤n ) and integer value k k (positive, negative or even zero) and change a l ,a l+1 ,…,a r  al,al+1,…,ar by k k each (i.e. a i :=a i +k ai:=ai+k for each l≤i≤…

题目大意: \(给你n个数a_i,给定一个m,你可以选择一个区间[l,r],让他们区间加一个任意数,然后询问一次操作完之后,最多能得到多少个m\) QWQ 考场上真的** 想了好久都不会,直到考试快结束才知道怎么做. 首先,根据题目,我们可以得知,假设我们修改了\([l,r]\)这个区间,那么最后的\(ans\)就应该是总的m的个数,减去区间中m的个数,加上区间内的众数的个数 QWQ 那么我们考虑怎么来处理这个. 首先,每个数字之间都是独立的. 所以我们可以预处理每一个数字出现的位置. 然后假设…

Description 给定一个长度为 \(n\) 的数列 \(a\) ,你可以任意选择一个区间 \([l,r]\) ,并给区间每个数加上一个整数 \(k\) ,求这样一次操作之后数列中最多有多少个数等于 \(c\). \(n,c,a_i\leq 10^5\) Solution 假设当前选择区间的右端点为 \(r\),那我们要强制将 \(a_r\) 这个元素变为 \(c\),不然可以通过让右端点 \(-1\) 使答案变得不劣. 同理,如果我们左端点 \(l\) 的元素 \(a_l\) 也要让其强…

Given an unsorted array of integers, find the length of longest continuous increasing subsequence. Example 1: Input: [1,3,5,4,7] Output: 3 Explanation: The longest continuous increasing subsequence is [1,3,5], its length is 3. Even though [1,3,5,7] i…

A. Increasing Sequence 题目连接: http://www.codeforces.com/contest/11/problem/A Description A sequence a0, a1, ..., at - 1 is called increasing if ai - 1 < ai for each i: 0 < i < t. You are given a sequence b0, b1, ..., bn - 1 and a positive integer…

［抄题］: Given an unsorted array of integers, find the length of longest continuous increasing subsequence (subarray). Example 1: Input: [1,3,5,4,7] Output: 3 Explanation: The longest continuous increasing subsequence is [1,3,5], its length is 3. Even t…

题目: Given an unsorted array of integers, find the length of longest continuous increasing subsequence (subarray). Example 1: Input: [1,3,5,4,7] Output: 3 Explanation: The longest continuous increasing subsequence is [1,3,5], its length is 3. Even tho…

Given an unsorted array of integers, find the length of longest continuous increasing subsequence. Example 1: Input: [1,3,5,4,7] Output: 3 Explanation: The longest continuous increasing subsequence is [1,3,5], its length is 3. Even though [1,3,5,7] i…