题意 给定一个包含\(n\)个数的序列\(a\),在其中任选若干个数,使得他们的和对\(m\)取模后最大.(\(n\leq 35\)) 题解 显然,\(2^n\)的暴枚是不现实的...,于是我们想到了折半枚举,分成两部分暴枚,然后考虑合并,合并的时候用two-pointers思想扫一遍就行了. 其实这是一道折半枚举+Two-Pointers的很好的练手题 //最近CodeForces有点萎,可能会JudgementError,但已经评测过了,能AC,多交几次应该可以 #include <cstd…
[CF888E]Maximum Subsequence 题意:给你一个序列{ai},让你从中选出一个子序列,使得序列和%m最大. n<=35,m<=10^9 题解:不小心瞟了一眼tag就一下子知道怎么做了,吓得我赶紧把tag屏蔽了. 我们将原序列拆成两半,每一部分都暴力搜索出所有的子序列之和,用set存起来.然后枚举前一半的所有子序列和,设其为x,则使得总和%m最大的右半部分子序列和一定是所有<m-x的数中最大的那个,在set里找一下前驱就行了. #include <cstdio&…
E. Maximum Subsequence time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given an array a consisting of n integers, and additionally an integer m. You have to choose some sequence of…
You are given an array a consisting of n integers, and additionally an integer m. You have to choose some sequence of indices \(b_1, b_2, ..., b_k (1 ≤ b_1 < b_2 < ... < b_k ≤ n)\) in such a way that the value of \(\sum^{k}_{i=1}a_{b_i}\) is maxi…
题目:http://codeforces.com/contest/888/problem/E 一看就是折半搜索?……然后排序双指针. 两个<m的数加起来如果>=m,一定不会更新答案.因为-m后的值比原来的两个数都小(a+b-m<a+m-m),不如它们去加0: 而如果两个数加起来<m,值比它们都大,可能更新答案. #include<iostream> #include<cstdio> #include<cstring> #include<al…
题意:给定n.m.有n个数,选出若干数加起来对m取模,求最大值 n<=35 如果直接暴力就是235,会T, 这里用到一个思想叫meet-in-the-middle, 就是把数列分成两半分别搜索,就是2n/2,然后为其中一个结果的所有值在另一个结果里找最优值, 这个操作可以用二分查找得到,所以可以用set维护 [链接]…
888E - Maximum Subsequence 思路:折半枚举. 代码: #include<bits/stdc++.h> using namespace std; #define ll long long #define pb push_back #define mem(a,b) memset(a,b,sizeof(a)) ; int a[N]; set<int>s; int main() { ios::sync_with_stdio(false); cin.tie(); i…
原题传送门 E. Maximum Subsequence time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given an array a consisting of n integers, and additionally an integer m. You have to choose some sequen…
Given a sequence of K integers { N1, N2, ..., NK }. A continuous subsequence is defined to be { Ni, Ni+1, ..., Nj } where 1 <= i <= j <= K. The Maximum Subsequence is the continuous subsequence which has the largest sum of its elements. For examp…
1​​, N2N_2N​2​​, ..., NKN_KN​K​​ }. A continuous subsequence is defined to be { NiN_iN​i​​, Ni+1N_{i+1}N​i+1​​, ..., NjN_jN​j​​ } where 1≤i≤j≤K1 \le i \le j \le K1≤i≤j≤K. The Maximum Subsequence is the continuous subsequence which has the largest sum…