题目大意: 有$n(n\le10^5)$个数$w_{1\sim n}(|w_i|\le10^9)$,并给定一个数$k(|k|\le10^9)$.$q(q\le10^5)$次询问,每次询问区间$[l,r]$中满足数字之和等于$k$的子区间数. 思路: 莫队卡常. #pragma GCC optimize("Ofast") #pragma GCC optimize("unroll-loops") #include<cmath> #include<cst…

cf 442 div2 F. Ann and Books(莫队算法) 题意: \(给出n和k,和a_i,sum_i表示前i个数的和,有q个查询[l,r]\) 每次查询区间\([l,r]内有多少对(i,j)满足l <= i <= j <= r 且 sum[j] - sum[i-1] = k\) 思路: 区间左右端点的挪动对答案的贡献符合加减性质,直接用莫队算法即可 复杂度\(O(n * sqrt(n) * log(maxsum))\) 过高 考虑先离散化预处理出所有位置 将\(log\)去…

转换成前缀和, 预处理一下然后莫队. #include<bits/stdc++.h> #define LL long long #define fi first #define se second #define mk make_pair #define PLL pair<LL, LL> #define PLI pair<LL, int> #define PII pair<int, int> #define SZ(x) ((int)x.size()) #de…

7 Must Read Python Books I started learning Python just two years ago. Coming from a C++ and Java background, it was easy to pick up the basic language features, but I wanted to learn more. What I did was order all the Python books that had good rati…

第三部分 NN-ANN 70年前的逆向推演 从这部分开始,调整一下视角主要学习神经网络算法,将其与生物神经网络进行横向的比较,以窥探一二. 现在基于NN的AI应用几乎是满地都是,效果也不错,这种貌似神奇的玩意怎么想出来的.个人不禁好奇,随后一通乱找.想理出来个线头,谁知一挖发现这线后面的故事太丰富,这里特意分享出来. 其实对神经元的认知是比较早的,在机制和功能方面多是偏向生物学解释,在这个领域最前面的自然是神经学和生物学家.在生物学框架下成果在二战前后推进速度飞快(二战期间德国和英美科研投入特别…

TCP/IP Fundamentals for Microsoft Windows: Overview https://technet.microsoft.com/en-us/library/bb726983.aspx The TCP/IP Guide: A Comprehensive, Illustrated Internet Protocols Reference https://www.amazon.com/exec/obidos/tg/detail/-/159327047X/qid=11…

题目链接: 传送门 Copying Books Time Limit: 3000MS     Memory Limit: 32768 KB Description Before the invention of book-printing, it was very hard to make a copy of a book. All the contents had to be re-written by hand by so called scribers. The scriber had b…

题目 Source http://www.lightoj.com/volume_showproblem.php?problem=1283 Description You are a librarian. You keep the books in a well organized form such that it becomes simpler for you to find a book and even they look better in the shelves. One day yo…

Copying  Books 题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=85904#problem/B 题目: Description Before the invention of book-printing, it was very hard to make a copy of a book. All the contents had to be re-written by hand by so calledscri…

Given an array A of integer with size of n( means n books and number of pages of each book) and k people to copy the book. You must distribute the continuous id books to one people to copy. (You can give book A[1],A[2] to one people, but you cannot g…