$1.\int{\frac{1}{\sqrt{x^2±a^2}}}dx=ln|x+\sqrt{x^2+a^2}|+C(a>0)$ $1.5.特别地, \int{\frac{1}{\sqrt{x(x+a)}}}dx=ln(\sqrt{x}+\sqrt{x+a})+C(a>0)$ $2.\int{tan^2(x)}dx=tanx-x+C$ $3.\int{\frac{1}{x^2+a^2}}dx=\frac{arctan{(\frac{x}{a})}}{a}+C$ $4.\int{\fra……

2 problems for div3 participants Bomb Defusing II Statement Find how many years in range [l,r] that it has Sept.1 as a weekend(Sunday and Saturday)? Example l=2017,r=2019 out=2 2018/9/1 is Saturday while 2019/9/1 is Sunday Constriants (Div2A-Div2B)……

思考题 within 5 min Bomb defusing 「Readers, please set up a 5-minute timer before you continue to read」 Green boy envied Orange Boy for having such a high rating. So he decided to send Orange Boy a present: a bomb! The bomb will explode in 5 minu……

APPROXIMATE PROBLEM WARNING Metro There are N metro stations in a city. The distance between each two station is a fixed integer x. Your task is to construct some metro lines across the stations. We define a cost from station A to station B as the ……

思考题 for bread Bread Story You have a piece of bread which can be seen as a N*M grid. You also have a bottle of jam. You want to put some jam on the bread to make the bread delicious. You can do the following two operations: Put 1 unit of jam on……

You can see the mod list here : modlist You can download the server pack here You can download the client pack here

XIZCM今天上课的时候叫我填个坑，我想如果以后高一要停课可以给个集训经验参考，就同意转载一下 以下两篇都是我之前写的blog 2019： zhengruioi 2019金华峰会游记 马上模拟赛开始了，zhengruioi.com 用起来了，这篇blog应该会被翻出来吧 我是跳跳 序： 今年是我第二年……

Added two extra stages, download and information at: https://blog.hellholestudios.club/archives/169 screenshot:

APPROXIMATE PROBLEM WARNING Graph There is a grid of size N*M. Each grid could be "#" or ".". You need to find the shortest path from (1,1) to (N,M) by walking on "." only. But you are NOT given the graph. You can only see the grids near you. That ……

「考える問題は簡単ですか」 Programming Detect You are given a directed graph G with N nodes and M edges. Each node has an operation, which could be "def sth" or "use sth". An array of nodes A is called Exceptional iff: - for each 1\leq i\leq |A|-1 ……