CF1336C Kaavi and Magic Spell 区间dp 题意 给一个长度为 \(n\) 的字符串 \(S\) 和一个长度为 \(m\) 的字符串\(T\) ,\(1\le m\le n\),然后开始有一个空串 \(A\),接下来可对 \(S\) 串进行 $n4 次操作: 把S的首个字符添加到A的开头然后删掉 把S的首个字符添加到A的尾端然后删掉 问在操作过程中使得 \(A\) 的前 \(m\) 个字符为 \(T\)(也就是前缀为 \(T\))的情况共有多少? 长度不同或者是操作序列…

LINK:Kaavi and Magic Spell 一打CF才知道自己原来这么菜 这题完全没想到. 可以发现 如果dp f[i][j]表示前i个字符匹配T的前j个字符的方案数 此时转移变得异常麻烦 状态转移一次变成了O(n). 会超时 而且这个状态的转移也是不正确的 可能当前的S字符串后面放了一些不能匹配的东西 但是此时却体现不出来. 那我们如何描述每次增加一个字符且和T匹配多少这种状态呢. 一个思路 先对于S串的某个i暴力枚举 其对应在T中的位置 这样的话dp就变成了 f[i][j][k]表…

虽然打的是div1,但最后半小时完全处于挂机状态,不会做1C,只有个 \(O(n^3)\) 的想法,水了水论坛,甚至看了一下div2的AB,所以干脆顺便写个div2的题解吧,内容看上去还丰富一些(X) A Ichihime and Triangle div2的日常构造题,想造个三角形的话,贪的思路就是让三条边长度尽可能接近,那就尽量把三个数都往中间凑一凑,然后发现\((b,c,c)\)是满足要求的,输出即可. 代码: #include<bits/stdc++.h> using namespac…

传送门 A. Linova and Kingdom 题意: 给定一颗以\(1\)为根的树,现在要选定\(k\)个结点为黑点,一个黑点的贡献为从他出发到根节点经过的白点数量. 问黑点贡献总和最大为多少. 思路: 最直接的想法黑点肯定是位于深度越深的点越好,并且有这样一个性质:假设我们选择了一个点,那么该点的所有后代也将会被选择. 一个黑点产生的贡献为其深度减去到根路径中黑点的数量. 直接按照上述思路贪心不好思考,考虑转化一下贡献的计算方法:我们减去黑点的数量时在其祖先结点再减.也就是说每个黑点会减…

A. Wizards' Duel Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/591/problem/A Description Harry Potter and He-Who-Must-Not-Be-Named engaged in a fight to the death once again. This time they are located at opposite ends of…

A. Wizards' Duel time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Harry Potter and He-Who-Must-Not-Be-Named engaged in a fight to the death once again. This time they are located at opposit…

McDonald’s Theory I use a trick with co-workers when we’re trying to decide where to eat for lunch and no one has any ideas. I recommend McDonald’s. An interesting thing happens. Everyone unanimously agrees that we can’t possibly go to McDonald’s, an…

Description A Horcrux is an object in which a Dark wizard or witch has hidden a fragment of his or her soul for the purpose of attaining immortality. Constructing a Horcrux is considered Dark magic of the foulest, most evil kind, as it violates laws…

D. Delivery Service 单测试点时限: 2.5 秒 内存限制: 512 MB EOJ Delivery Service Company handles a massive amount of orders in our nation. As is well known, our nation has ncities, with n−1 bi-directional paths connecting them, forming a tree. The length of the i…

Description A Horcrux is an object in which a Dark wizard or witch has hidden a fragment of his or her soul for the purpose of attaining immortality. Constructing a Horcrux is considered Dark magic of the foulest, most evil kind, as it violates laws…

Index of contents Setting up the MinGW 64 environment Step 1) building libiconv Step 2) building libz Step 3) building libjpeg Step 4) building libpng Step 5) building libtiff Step 6) building libproj Step 7) building libgeotiff Step 8) building libg…

https://medium.com/flutter-community/flutter-ide-shortcuts-for-faster-development-2ef45c51085b If you’re new to Flutter development then you must be cribbing about the nested structures, how hard it is to add or remove widgets from the middle of the…

去年742,今年72,也算一种小小的进步. 明年前30(笑 1. Drawing Rooted Binary Trees 给定一个树的中序和前序的遍历,要求输出这棵树(包括空格的) #include <iostream>// #include <string.h>// #include <stdio.h>// #include <stdlib.h>// #include <math.h>// #include <string.h>//…

MMDeploy的TensorRT教程 Step1: 创建虚拟环境并且安装MMDetection conda create -n openmmlab python=3.7 -y conda activate openmmlab conda install pytorch==1.8.0 torchvision==0.9.0 cudatoolkit=10.2 -c pytorch -y # install mmcv pip install mmcv-full==1.4.0 -f https://do…

NOTE: This specific issue was fixed before the launch of Privacy-Preserving Contact Tracing in iOS 13.5 in May 2020. In this demo I remotely trigger an unauthenticated kernel memory corruption vulnerability which causes all iOS devices in radio-proxi…

A. Magic Spheres   Carl is a beginner magician. He has a blue, b violet and c orange magic spheres. In one move he can transform two spheres of the same color into one sphere of any other color. To make a spell that has never been seen before, he nee…

A. Magic Spheres Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://www.codeforces.com/contest/606/problem/A Description Carl is a beginner magician. He has a blue, b violet and c orange magic spheres. In one move he can transform two spheres of the…

原文:https://robots.thoughtbot.com/the-magic-behind-configure-make-make-install#where-do-these-scripts-come-from The magic behind configure, make, make install George Brocklehurst  January 19, 2015 UNIX   + If you've used any flavour of Unix for develo…

链接:http://acm.hdu.edu.cn/showproblem.php?pid=6508 题目: Problem Description Shadowverse is a funny card game. One day you are playing a round of this game.You have n cards, each with two attributes wi and xi. If you use card i, you will cost wi points…

D. Magic Breeding link http://codeforces.com/contest/878/problem/D description Nikita and Sasha play a computer game where you have to breed some magical creatures. Initially, they have k creatures numbered from 1 to k. Creatures have n different cha…

D. Magic Breeding time limit per test 4 seconds memory limit per test 1024 megabytes input standard input output standard output Nikita and Sasha play a computer game where you have to breed some magical creatures. Initially, they have kcreatures num…

Spell Boost 时间限制: 1 Sec  内存限制: 128 MB 题目描述 Shadowverse is a funny card game. One day you are playing a round of this game.You have n cards, each with two attributes wi and xi. If you use card i, you will cost wi points of power and cause xi damage to…

Magic Spheres Time Limit: 2000MS   Memory Limit: 262144KB   64bit IO Format: %I64d & %I64u Submit Status Description Carl is a beginner magician. He has a blue, b violet and c orange magic spheres. In one move he can transform two spheres of the same…

Recently Petya walked in the forest and found a magic stick. Since Petya really likes numbers, the first thing he learned was spells for changing numbers. So far, he knows only two spells that can be applied to a positive integer: If the chosen numbe…

D. Magic Numbers time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Consider the decimal presentation of an integer. Let's call a number d-magic if digit d appears in decimal presentation of…

A magic index in an array A[0...n-1] is defined to be an index such that A[i] = i. Given a sorted array of distinct integers, write a method to find a magic index, if one exists, in array A. FOLLOW UP What if the values are not distinct? public int g…

介绍 在Python中,所有以"__"双下划线包起来的方法,都统称为"Magic Method",例如类的初始化方法 __init__ ,Python中所有的魔术方法均在官方文档中有相应描述,但是对于官方的描述比较混乱而且组织比较松散.很难找到有一个例子. 构造和初始化 每个Pythoner都知道一个最基本的魔术方法, __init__ .通过此方法我们可以定义一个对象的初始操作.然而,当调用 x = SomeClass() 的时候, __init__ 并不是第一个…

F. Heroes of Making Magic III time limit per test:3 seconds memory limit per test:256 megabytes input:standard input output:standard output I’m strolling on sunshine, yeah-ah! And doesn’t it feel good! Well, it certainly feels good for our Heroes of…

Magic boy Bi Luo with his excited tree Problem Description Bi Luo is a magic boy, he also has a migic tree, the tree has N nodes , in each node , there is a treasure, it's value is V[i], and for each edge, there is a cost C[i], which means every time…

代码: int i = *reinterpret_cast<int*>(&(d += 6755399441055744.0)); 知识点: 1.reinterpret_cast<type_id> expression:type_id 必须是一个指针.引用.算术类型.函数指针或者成员指针.它可以把一个指针转换成一个整数,也可以把一个整数转换成一个指针(先把一个指针转换成一个整数,再把该整数转换成原类型的指针,还可以得到原先的指针值). 只是将bit表示进行了重新解读,不改变位…