B. Dima and Sequence Dima got into number sequences. Now he's got sequence a1, a2, ..., an, consisting of n positive integers. Also, Dima has got a function f(x), which can be defined with the following recurrence: f(0) = 0; f(2·x) = f(x); f(2·x + 1)…

D. The Child and Sequence time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output At the children's day, the child came to Picks's house, and messed his house up. Picks was angry at him. A lot of…

E. Dima and Horses Dima came to the horse land. There are n horses living in the land. Each horse in the horse land has several enemies (enmity is a symmetric relationship). The horse land isn't very hostile, so the number of enemies of each horse is…

有N<3000只宠物要喂,每次只能喂一只,每喂一只宠物,宠物的满足度取决于: 1 紧靠的两个邻居都没喂,a[i] 2 邻居中有一个喂过了,b[i] 3 两个邻居都喂过了,c[i] 把所有宠物喂一遍,得到的满足度之和最大为多少. =========== 动态规划, 动态转移方程的难点 在于 搞清楚“无后效性” =========== dp[i]为从i开始往后喂 以第一只宠物为例,可以选择 1) 先喂第一只, a[1] + 第二只排在第一只后面的最大值.注意,先喂第一只,只会影响第二只. 2)先喂第…

之前几乎没写过什么这种几何的计算题.在众多大佬的博客下终于记起来了当时的公式.嘚赶快补计算几何和概率论的坑了... 这题的要求,在对两圆相交的板子略做修改后,很容易实现.这里直接给出代码.重点的部分有:两圆在相离(或外交)时输出第一个圆的面积.内涵(或内切)则需要分类讨论,是羊的圈大.还是狼的圈大.以下是代码: #include<iostream> #include<cmath> #include<stdio.h> using namespace std; int ma…

题目链接: http://codeforces.com/problemset/problem/272/D D. Dima and Two Sequences time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Little Dima has two sequences of points with integer coordinates: sequence (a1, 1), (a2, 2), ..., (an, …

又水了一发Codeforce ,这次继续发发题解顺便给自己PKUSC攒攒人品吧 CodeForces 438C:The Child and Polygon: 描述:给出一个多边形,求三角剖分的方案数(n<=200). 首先很明显可能是区间dp,我们可以记f[i][j]为从i到j的这个多边形的三角剖分数,那么f[i][j]=f[i][k]*f[j][k]*(i,j,k是否为1个合格的三角形) Code: #include<cstdio> #include<iostream> #…

An arithmetic progression is such a non-empty sequence of numbers where the difference between any two successive numbers is constant. This constant number is called common difference. For example, the sequence 3, 7, 11, 15 is an arithmetic progressi…

You are given a sequence of numbers a1, a2, ..., an, and a number m. Check if it is possible to choose a non-empty subsequence aij such that the sum of numbers in this subsequence is divisible by m. Input The first line contains two numbers, n and m…

You want to perform the combo on your opponent in one popular fighting game. The combo is the string s consisting of n lowercase Latin letters. To perform the combo, you have to press all buttons in the order they appear in s. I.e. if s="abca" t…