ARC 122 简要题解 传送门 A - Many Formulae 考虑对于每个数分别算其贡献. 通过枚举该数前面的符号,借助一个非常简单的 \(\mathrm{DP}\)(\(f_{i,0/1}\) 表示 \(i\) 个符号,最后一个符号为 \(+/-\) 的方案数),我们可以很轻松的求出一个数对最终答案的贡献. 总时间复杂度为 \(O(n)\). /*---Author:HenryHuang---*/ #include<bits/stdc++.h> using namespace std…

Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k ≤ n-1 else return…

Given an integer matrix, find the length of the longest increasing path. From each cell, you can either move to four directions: left, right, up or down. You may NOT move diagonally or move outside of the boundary (i.e. wrap-around is not allowed). E…

Given an unsorted array of integers, find the length of longest increasing subsequence. For example, Given [10, 9, 2, 5, 3, 7, 101, 18], The longest increasing subsequence is [2, 3, 7, 101], therefore the length is 4. Note that there may be more than…

error: unable to rewind rpc post data - try increasing http.postBuffererror: RPC failed; curl 56 Recv failure: Connection was abortedfatal: The remote end hung up unexpectedly 当使用git 一次提交的数据过大时,会出现以上错误,按照提示我们增大postBuffer git config --global http.post…

1. Description Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k ≤…

Longest Increasing Subsequence(LIS) 一个美丽的名字 非常经典的线性结构dp [朴素]:O(n^2) d(i)=max{0,d(j) :j<i&&a[j]<a[i]}+1 直接两个for [二分查找优化]:O(n^2) g(i):d值为i的最小的a  每次更新然后lower_bound即可 ［大于等于］ lower_boundReturn iterator to lower bound Returns an iterator pointing…

Given a sequence of integers, find the longest increasing subsequence (LIS). You code should return the length of the LIS. Have you met this question in a real interview?     Example For [5, 4, 1, 2, 3], the LIS  is [1, 2, 3], return 3 For [4, 2, 4,…

Given a sequence of integers, find the longest increasing subsequence (LIS). You code should return the length of the LIS. Example For [5, 4, 1, 2, 3], the LIS  is [1, 2, 3], return 3 For [4, 2, 4, 5, 3, 7], the LIS is [4, 4, 5, 7], return 4 Challeng…

Given an integer matrix, find the length of the longest increasing path. From each cell, you can either move to four directions: left, right, up or down. You may NOT move diagonally or move outside of the boundary (i.e. wrap-around is not allowed). E…