首先应该保证二进制最高位尽量高,而位数最高的数乘x以后位数任然是最高的,所以一定一个数是连续k次乘x. 当出现多个最高位的相同的数就枚举一下,先预处理一下前缀后缀即可. #include<bits/stdc++.h> using namespace std; ; int a[maxn]; int pf[maxn],sf[maxn]; int main() { int n,k,x; scanf("%d%d%d",&n,&k,&x); ; i <=…

C. Weakness and Poorness Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/578/problem/C Description You are given a sequence of n integers a1, a2, ..., an. Determine a real number x such that the weakness of the sequence a1 -…

B. "Or" Game Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/578/problem/B Description You are given n numbers a1, a2, ..., an. You can perform at most k operations. For each operation you can multiply one of the number…

题目链接:http://codeforces.com/contest/578/problem/B 题目大意:现在有n个数,你可以对其进行k此操作,每次操作可以选择其中的任意一个数对其进行乘以x的操作.思路:最先想到的办法是贪心,也就是选择数组中最大的那个数对它进行k次乘以x的操作.但是这种方法在有的时候会出现错误,如测试数据的第三组:2 1 212 9这种情况下有2个数,我能够对其进行1次乘以2的操作,如果以之前贪心的方法,选择12乘以2,那么得到的结果(12*2)|9=25,但是如果选择9乘以…

E. Weakness and Poorness time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a sequence of n integers a1, a2, ..., an. Determine a real number x such that the weakness of the seq…

A. Raising Bacteria time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are a lover of bacteria. You want to raise some bacteria in a box. Initially, the box is empty. Each morning, you can…

D. "Or" Game time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given n numbers a1, a2, ..., an. You can perform at most k operations. For each operation you can multiply one of…

E. Weakness and Poorness time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a sequence of n integers a1, a2, ..., an. Determine a real number x such that the weakness of the seq…

显然f(x)是个凹函数,三分即可,计算方案的时候dp一下.eps取大了会挂精度,指定循环次数才是正解. #include<bits/stdc++.h> using namespace std; ; ; double a[maxn]; double d1[maxn],d2[maxn]; int n; inline double cal(double x) { ., a2 = .; ; i <= n; i++){ d1[i] = max(.,d1[i-])+a[i]-x; a1 = max(…

题目中给出的函数具有周期性,总可以移动到第一个周期内,当然,a<b则无解. 假设移动后在上升的那段,则有a-2*x*n=b,注意限制条件x≥b,n是整数,则n≤(a-b)/(2*b).满足条件的x≥(a-b)/(2*n) 假设在下降的那段,2*x-(a-2*x*n)=b,n+1≤(a+b)/(2*b),x≥(a+b)/(2*(n+1)) 两者取最小值 #include<bits/stdc++.h> using namespace std; int main() { int a,b; sc…

一部分题解,算是自己SB了 上午的TC 也是这样 写好了代码,却一直没注意细节,然后以为错了. 此处省100字,ps 貌似紫了,作为一个老菜鸡,终于紫了 A,B 都是语文题 C: 给以一个三角形一样的图,判断点(a,b)是否在图中,我是这样判断的: 前一半是k*2*x+b=a;求最小的x,这里二分,但是注意k=0,所以你特判掉: 后一半是:2*(k+1)=a+b;二分类似 D:坐等官方题解,不靠谱系列:我试了很多方法: 做法:只可能是一个数*x^k: 之前以为是最大数*x^k ,但是错的 想想:…

                                                                        D. "Or" Game                                                                             time limit per test 2 seconds You are given n numbers a1, a2, ..., an. You can perfo…

                                                                       C. A Problem about Polyline                                                                                time limit per test 1 second                                            …

                                                                  B. Finding Team Member                                                                               time limit per test 2 seconds                                                      …

1.前言 虽然这次我依旧没有参加正式比赛,但是事后还是看了看题目的...一般不怎么刷Codeforces. A.Raising Bacteria You are a lover of bacteria. You want to raise some bacteria in a box. Initially, the box is empty. Each morning, you can put any number of bacteria into the box. And each night…

解题思路:就是求数 n 对应的二进制数中有多少个 1 #include <iostream> #include<cstdio> using namespace std; int main(){ int n; cin>>n; ; // while(n){//这也是一种好的方法 // n = n&(n-1); // ++ans; // } while(n){ ) ++ans; n>>=; } cout<<ans<<endl; ;…

D. "Or" Game time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given n numbers a1, a2, ..., an. You can perform at most k operations. For each operation you can multiply one of…

题意:一个等腰直角三角形一样的周期函数(只有x+轴),经过给定的点(a,b),并且半周期为X,使X尽量大,问X最大为多少? 如果a=b,结果就为b 如果a<b无解. 否则,b/(2*k*x-a)=1或者b/(a-2*k*x)=1;以前者为例,x=(a-b)/(2*k).x越小越好,那么k尽量大,但是K过大,x就会小于b,x小于b就无法穿过(a,b).k要大又不能过大就满足二分的要求,就能二分. 乱码: //#pragma comment(linker,"/STACK:1024000000,…

题意:一个数组arr,一个数字x,要使arr-x的最大子段最小,问该最小值. 三分x,复杂度logn,内层是最大子段的模板,只能用n复杂度的.因为是绝对值最大,正负各求一次,取大的.精度卡得不得了,要1e-12左右才能过.看着数据才调出精度的. 乱码: //#pragma comment(linker,"/STACK:1024000000,1024000000") #include<iostream> #include<cstdio> #include<s…

题意:n个数字,最多操作k次,每次乘x,要使结果数组的与值最大. 能推断出结果是对一个元素操作k次,并且这个元素的二进制最高位比较大.并不一定是取最大的,比如1100和1010,乘以一次2,两种选法分别为11000|1010=11010,:::1100|10100=11100后者更大. 有没有可能k次乘在不同的数字上呢?不可能.如果有3个数字abc二进制最高位都是第5位,k=3,x=2,假如乘了一次a,再乘两次a,与的结果是8位.如果放弃a,去乘别的,只有7位以下. 实现过程中,用一个数组arr…

题目:http://codeforces.com/contest/389/problem/C 题意:给n个箱子,给n个箱子所能承受的重量,每个箱子的重量为1: 很简单的贪心,比赛的时候没想出来...... 先从小到大排一下序,然后从最上层向下找,只要能承受住重量就行.而且因为已经排序了找的都是尽量小的... #include <iostream> #include <cstdio> #include <cstring> #include <cstdlib>…

A. Combination Lock time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output Scrooge McDuck keeps his most treasured savings in a home safe with a combination lock. Each time he wants to put there…

A. Straight «A» time limit per test:1 second memory limit per test:256 megabytes input:standard input output:standard output Noora is a student of one famous high school. It's her final year in school — she is going to study in university next year.…

题目:http://codeforces.com/contest/1154/problem/F 题意:给你n个商品,然后还有m个特价活动,你买满x件就把你当前的x件中最便宜的y件价格免费,问你买k件花最少的钱是多少 思路:首先这个特价活动就像点外卖一样满多少减多少,你可以分几次来使用同一个优惠或者不同的优惠,然后我们我们分析三个点 1,那个特价活动中x>k的我们肯定都不会使用,因为那个时候已经买满了k件 2,我们肯定是买最便宜的k件来使用特价活动 3,我们其实可以当成分开几组来使用优惠,就像外卖…

https://codeforces.com/contest/1059/problem/E 题意 给出一棵树,每个点都有一个权值,要求你找出最少条链,保证每个点都属于一条链,而且每条链不超过L个点 和 每条链的权值和不超过S 题解 对于儿子来说,父亲节点只有一个,所以没有决策点.可以从下往上处理出,每个节点最远能爬到那个节点(过程就是倍增) 然后从下往上贪 (选择往上走的远的子节点) #include<bits/stdc++.h> #define ll long long #define pb…

D. Dasha and Very Difficult Problem 题目连接: http://codeforces.com/contest/761/problem/D Description Dasha logged into the system and began to solve problems. One of them is as follows: Given two sequences a and b of length n each you need to write a se…

F. Ivan and Burgers 题目链接:https://codeforces.com/contest/1100/problem/F 题意: 给出n个数,然后有多个询问,每次回答询问所给出的区间的异或和最大值. 题解: 考虑离线做法,先把所有的询问区间按照右端点进行排序,然后从1开始逐个将ai插入,插入线性基的同时记录一下位置,最后扫一下,看看哪些的位置是不小于li的即可加入答案. 这种做法在时间复杂度上面是可行的,但是需要注意的是,如果在i这个位置插入最高位为x的线性基,同时在j这个位…

题目链接:http://codeforces.com/contest/761/problem/D D. Dasha and Very Difficult Problem time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Dasha logged into the system and began to solve problem…

原博主:https://blog.csdn.net/amovement/article/details/80358962 B. Bus of Characters time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output In the Bus of Characters there are nn rows of seat, each h…

传送门 Description A long time ago, in a galaxy far far away two giant IT-corporations Pineapple and Gogol continue their fierce competition. Crucial moment is just around the corner: Gogol is ready to release it's new tablet Lastus 3000. This new devic…