[Codeforces 1199C]MP3(离散化+二分答案) 题面 给出一个长度为n的序列\(a_i\)和常数I,定义一次操作[l,r]可以把序列中<l的数全部变成l,>r的数全部变成r.每次操作的代价为改变数的个数.问:要让操作后序列里不同数的个数\(k\)满足$n \lceil \log _2 k\rceil \leq 8I $,操作的最小代价 分析 首先把a离散化,这样[l,r]都在\(10^5\)的级别.枚举l,发现r显然有单调性.操作后不同数的个数随r的增大而减小(考虑极端情况l=…
You have n devices that you want to use simultaneously. The i-th device uses ai units of power per second. This usage is continuous. That is, in λ seconds, the device will use λ·ai units of power. The i-th device currently has bi units of power store…
传送门 二分答案好题. 题意简述:要求支持动态在一个数列队尾加入一个新的数(保证数列单增),查询所有子数列的 最大值减平均值 的最大值. 然而网上一堆高人是用三分做的. 我们先考虑当前的答案有可能由什么构成. 加入最后一个数之前的最大值. 加入最后一个数之后,以最后一个数为最大值的值. 于是问题变成了去求min{(∑j=1iai)+ani+1}min\{\frac{(\sum_{j=1}^ia_i)+a_n}{i+1}\}min{i+1(∑j=1i​ai​)+an​​} 然后令bi=(∑j=1i…
Digital collectible card games have become very popular recently. So Vova decided to try one of these. Vova has n cards in his collection. Each of these cards is characterised by its power pi, magic number ci and level li. Vova wants to build a deck…
Fibonacci-ish Yash has recently learnt about the Fibonacci sequence and is very excited about it. He calls a sequence Fibonacci-ish if the sequence consists of at least two elements f0 and f1 are arbitrary fn + 2 = fn + 1 + fn for all n ≥ 0. You are…
https://codeforc.es/contest/1199/problem/C 擦,最后移位运算符溢出了,真的蠢. 肯定是选中间的连续的某段是最优的,维护这个段的长度和其中的元素种类就可以了.小心x可能很大导致溢出. #include<bits/stdc++.h> using namespace std; typedef long long ll; inline int read() { int x = 0; int f = 0; char c; do { c = getchar();…
[题目链接] http://codeforces.com/problemset/problem/700/A [题目大意] 有一辆限载k人速度为v2的车,n个步行速度均为v1的人要通过一段长度为l的距离,每个人只能上车一次,车可以来回走,问所有人到达目的地所需要的最短时间是多少 [题解] 因为车可以载k个人,所以,我们把人k个为一组分成(n+k-1)/k组,记为p吗,设需要的最短时间为t,每个人在车上待的时间为t2,那么可以列方程v1*(t-t2)+v2*t2=l,我们可以发现t2可以用t来表示,…
链接:http://codeforces.com/contest/484/problem/E 题意: 给你n个数的,每个数代表高度: 再给出m个询问,每次询问[l,r]区间内连续w个数的最大的最小值: 思路: 因为查询的到的值一定是输入的其中一个,那么我们可以二分答案,判断二分得到的答案是否符合,那么在这里我们就只需要找到某个数x,查询区间[l,r]有多少个连续的数大于x,这个操作只需要将高度从小到达排序,倒着插入主席树中,值设为1,那么只要维护有多少个连续的1(线段树区间合并的方法),就代表有…
n people are standing on a coordinate axis in points with positive integer coordinates strictly less than 106. For each person we know in which direction (left or right) he is facing, and his maximum speed. You can put a bomb in some point with non-n…
There are n people and k keys on a straight line. Every person wants to get to the office which is located on the line as well. To do that, he needs to reach some point with a key, take the key and then go to the office. Once a key is taken by somebo…