Codeforces #345 Div.1 打CF有助于提高做题的正确率. Watchmen 题目描述:求欧拉距离等于曼哈顿距离的点对个数. solution 签到题,其实就是求有多少对点在同一行或同一列. 时间复杂度:\(O(nlogn)\) Image Preview 题目描述:给定看一张照片的时间,翻页的时间,把图片翻转的时间.一开始屏幕显示第一张照片,可以向左或向右翻,不能跳过还没有看过的图片,方向不对的图片要先翻转再看,看过的不消耗翻转时间与看照片时间,问在一定时间内,最多能看多少张照…

Vasya has decided to build a zip-line on trees of a nearby forest. He wants the line to be as long as possible but he doesn't remember exactly the heights of all trees in the forest. He is sure that he remembers correct heights of all trees except, p…

 cf之路,1,Codeforces Round #345 (Div. 2) ps:昨天第一次参加cf比赛,比赛之前为了熟悉下cf比赛题目的难度.所以做了round#345连试试水的深浅.....       其实这个应该是昨天就写完的,不过没时间了,就留到了今天.. 地址:http://codeforces.com/contest/651/problem/A A. Joysticks time limit per test 1 second memory limit per test 256…

Codeforces #344 Div.2 Interview 题目描述:求两个序列的子序列或操作的和的最大值 solution 签到题 时间复杂度:\(O(n^2)\) Print Check 题目描述:有一个棋盘,对其进行染色,每次染一行或一列,后来的颜色会覆盖原来的颜色,输出最后的棋盘. solution 题解用二维线段树,其实可以不用. 对染色进行离线操作,那么染过的格子.行.列就不用再染了.所以每个格子可以记录四个指针,分别是行前驱,行后继,列前驱列后继,染色时按照这个跳着来染就好了.…

Codeforces Beta Round #27 (Codeforces format, Div. 2) http://codeforces.com/contest/27 A #include<bits/stdc++.h> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define sqr(x) ((x)*(x)) #define maxn 1000005 typ…

Codeforces#441 Div.2 四小题 链接 A. Trip For Meal 小熊维尼喜欢吃蜂蜜.他每天要在朋友家享用N次蜂蜜 , 朋友A到B家的距离是 a ,A到C家的距离是b ,B到C家的距离是c  (A- >Rabbit   B- >Owl    C ->Eeyore),他不能连续两顿饭都在同一位朋友家里蹭 他现在位于A的家里, 请问他一天最少要跑多少路. 当然是要找一条最短的路折返跑了啊,是不是很简单. #include<bits/stdc++.h> us…

codeforces #592(Div.2) A Pens and Pencils Tomorrow is a difficult day for Polycarp: he has to attend a lectures and b practical classes at the university! Since Polycarp is a diligent student, he is going to attend all of them. While preparing for th…

codeforces #578(Div.2) A. Hotelier Amugae has a hotel consisting of 1010 rooms. The rooms are numbered from 00 to 99 from left to right. The hotel has two entrances - one from the left end, and another from the right end. When a customer arrives to t…

codeforces #577(Div.2) A  Important Exam A class of students wrote a multiple-choice test. There are nn students in the class. The test had mm questions, each of them had 55 possible answers (A, B, C, D or E). There is exactly one correct answer for…

http://codeforces.com/contest/599/problem/D 题意:给出总的方格数x,问有多少种不同尺寸的矩形满足题意,输出方案数和长宽(3,5和5,3算两种) 思路:比赛的时候gg了..其实稍微在纸上推一下.就会得到对于n,m的矩形,一共会有-n*n*n+3*n*n*m+n+3*n*m的方格.数量级是n3. 我们可以实际跑一遍.发现对于x1E18的数量级,n不会超过1442550,1E6,可以搞. 需要注意的是,一个是会爆int,所以记得用long long 另一个是…