ICPC 2019 徐州网络赛 比赛时间:2019.9.7 比赛链接:The Preliminary Contest for ICPC Asia Xuzhou 2019 赛后的经验总结 // 比赛完才反应过来没看完全部题, J题树形dp没写太亏了... // 几何旋律AK了,太强了Orz // 虽然我们队A了8题,但如果时间分配好,认真读题避免看错题的话,应该至少多A一题 A. Who is better? 题意 两个人玩游戏,谁先消灭完敌人就赢.两条规则:1. 第一个人不能全部消灭完: 2.…

You are given a point set with nn points on the 2D-plane, your task is to find the smallest number of points you need to add to the point set, so that all the points in the set are center symmetric. All the points are center symmetric means that you…

XKC , the captain of the basketball team , is directing a train of nn team members. He makes all members stand in a row , and numbers them 1 \cdots n1⋯n from left to right. The ability of the ii-th person is w_iwi​ , and if there is a guy whose abili…

Carneginon was a chic bard. But when he was young, he was frivolous and had joined many gangs. Recently, Caneginon was to be crowned, because the king was shocked by his poems and decided to award him the gold medal lecturer. Therefore, Most of peopl…

The hot summer came so quickly that Xiaoming and Xiaohong decided to buy a big and sweet watermelon. But they are two very strange people. They are even-numbered enthusiasts. They want to cut the watermelon in two parts, and each part weighs two time…

题目链接:https://nanti.jisuanke.com/t/41384 这题暴力能过,我用的是并查集的思想,这个题的数据是为暴力设置的,所以暴力挺快的,但是当他转移的点多了之后,我觉得还是我这种方法更好一点.注意这里一定要用内部是hash的unordered_map 做,因为查询为o(1) #include <iostream> #include <algorithm> #include <cstdio> #include <cstring> #in…

A After Asgard was destroyed, tanker brought his soldiers to earth, and at the same time took on the important task of protecting the peace of the earth. The best two solders were lb and zgx, were very capable, but they always disliked each other. Ho…

query \[ Time Limit: 2000 ms \quad Memory Limit: 262144 kB \] 题意 补题才发现比赛的时候读了一个假题意.... 给出长度为 \(n\) 的排列,在给出 \(m\) 次询问,每次询问有一对 \(l.r\),问满足 \(min(ai, aj) = gcd(ai, aj)\) 的 \(pair(i, j)\) 对数. 思路 考虑离线做 先把每个数出现的位置记录下来,然后预处理出所有的 \(pair\). 对于一个数字 \(x\),其满足条件…

I. query 比赛时候没有预处理因子疯狂t,其实预处理出来因子是\(O(nlog(n))\)级别的 每个数和他的因子是一对偏序关系,因此询问转化为(l,r)区间每个数的因子在区间(l,r)的个数 预处理出来每个位置上的数所有因子的位置,用可持久化线段树维护,区间询问 #include<bits/stdc++.h> #define ll long long #define mk make_pair #define ft first #define se second #define pii…

题意: 先有\(n=p_1^{k_1}p_2^{k_2}\cdots p_m^{k_m}\),定义\(f(n)=k_1+k_2+\cdots+k_m\). 现在计算 \[ \sum_{i=1}^nf(i!)\% 998244353 \] 思路: 首先注意到\(f\)函数有这样一个性质:\(f(ab)=f(a)+f(b)\). 那么我们化简所求式子有: \[ \begin{aligned} &\sum_{i=1}^nf(i!)\\ =&\sum_{i=1}^n\sum_{j=1}^if(j)…