C. Block Towers 题目连接: http://www.codeforces.com/contest/626/problem/C Description Students in a class are making towers of blocks. Each student makes a (non-zero) tower by stacking pieces lengthwise on top of each other. n of the students use pieces…

  C. Block Towers   time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Students in a class are making towers of blocks. Each student makes a (non-zero) tower by stacking pieces lengthwise on…

在家补补题   模拟 A - Robot Sequence #include <bits/stdc++.h> char str[202]; void move(int &x, int &y, char ch) { if (ch == 'U') x--; if (ch == 'D') x++; if (ch == 'L') y--; if (ch == 'R') y++; } int main(void) { int n; scanf ("%d", &…

题目链接:http://codeforces.com/contest/626/problem/C 题意就是给你n个分别拿着2的倍数积木的小朋友和m个分别拿着3的倍数积木的小朋友,每个小朋友拿着积木的数量互不相同,求小朋友中拿着最大积木数的最小的情况(有点绕). 那最坏的情况就是2n或者3m,假设最大的积木数为x,x肯定能被2或3整除,那么x/2就是2的倍数个数,x/3就是3的倍数的个数,x/6就是6的倍数的个数. 因为这个数据量很小,那么只要暴力寻找刚好符合x/3 + x/2 - x/6 >=…

E. Simple Skewness 题目连接: http://www.codeforces.com/contest/626/problem/E Description Define the simple skewness of a collection of numbers to be the collection's mean minus its median. You are given a list of n (not necessarily distinct) integers. Fi…

C. Lieges of Legendre 题意:给n,m表示有n个为2的倍数,m个为3的倍数:问这n+m个数不重复时的最大值 最小为多少? 数据:(0 ≤ n, m ≤ 1 000 000, n + m > 0) ps:很水的题,主要是策略: 思路:由于里面每隔6就会重复一次,不好直接模拟,并且模拟的效率很低,那就二分吧!二分即上界为2单独的最大倍数与3单独时的最大倍数之和,下界为前面二者的max;之后利用判断是否mid/2 >= n && mid/3 >= m &am…

F. Group Projects   There are n students in a class working on group projects. The students will divide into groups (some students may be in groups alone), work on their independent pieces, and then discuss the results together. It takes the i-th stu…

G. Raffles 题目连接: http://www.codeforces.com/contest/626/problem/G Description Johnny is at a carnival which has n raffles. Raffle i has a prize with value pi. Each participant can put tickets in whichever raffles they choose (they may have more than o…

F. Group Projects 题目连接: http://www.codeforces.com/contest/626/problem/F Description There are n students in a class working on group projects. The students will divide into groups (some students may be in groups alone), work on their independent piec…

D. Jerry's Protest 题目连接: http://www.codeforces.com/contest/626/problem/D Description Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andrew and Jerry draw randomly without replaceme…

B. Cards 题目连接: http://www.codeforces.com/contest/626/problem/B Description Catherine has a deck of n cards, each of which is either red, green, or blue. As long as there are at least two cards left, she can do one of two actions: take any two (not ne…

A. Robot Sequence 题目连接: http://www.codeforces.com/contest/626/problem/A Description Calvin the robot lies in an infinite rectangular grid. Calvin's source code contains a list of n commands, each either 'U', 'R', 'D', or 'L' - instructions to move a…

F - Group Projects 题目大意:给你n个物品, 每个物品有个权值ai, 把它们分成若干组, 总消耗为每组里的最大值减最小值之和. 问你一共有多少种分组方法. 思路:感觉刚看到的时候的想法是先排好序, dp[ i ][ j ][ k ]表示已经划分了 i 个, 并且分成了 j 组, 目前为止的总消耗为k的方案总数. 但是这个状态没有办法转移, 题解提供了一种将贡献分段的方法, 比如说原数组为1 2 3 6 7 8 10, 其中一组里面有 1 3 7 8 那么我们不是 直接计算出(8…

Preorder Test 题目连接: http://www.codeforces.com/contest/627/problem/D Description For his computer science class, Jacob builds a model tree with sticks and balls containing n nodes in the shape of a tree. Jacob has spent ai minutes building the i-th ba…

暴力 A - Orchestra import java.io.*; import java.util.*; public class Main { public static void main(String[] args) { Scanner cin = new Scanner (System.in); int r = cin.nextInt (); int c = cin.nextInt (); int n = cin.nextInt (); int k = cin.nextInt ();…

传送门:http://codeforces.com/contest/755 A题题意是给你一个数字n,让你找到一个数字m,使得n*m+1为合数,范围比较小,直接线性筛出1e6的质数,然后暴力枚举一下就好了. #include <iostream> #include <cstdio> #include <cstring> #include <cmath> #include <algorithm> #include <vector> #i…

题目链接:http://codeforces.com/contest/755 本蒟蒻做了半天只会做前两道题.. A. PolandBall and Hypothesis 题意:给出n,让你找出一个m,使n*m+1不是素数. 数据很小,直接暴力枚举. #include<cstdio> #include<iostream> #include<cmath> using namespace std ; bool prime( int n ) { for( int i = 2 ;…

E - Preorder Test 思路:想到二分答案了之后就不难啦, 对于每个答案用树形dp取check, 如果二分的值是val, dp[ i ]表示 i 这棵子树答案不低于val的可以访问的 最多节点, 第二次dfs求出以每个点为根的答案. #include<bits/stdc++.h> #define LL long long #define fi first #define se second #define mk make_pair #define PII pair<int,…

C. Package Delivery 题目连接: http://www.codeforces.com/contest/627/problem/C Description Johnny drives a truck and must deliver a package from his hometown to the district center. His hometown is located at point 0 on a number line, and the district cen…

D. Factory Repairs 题目连接: http://www.codeforces.com/contest/635/problem/D Description A factory produces thimbles in bulk. Typically, it can produce up to a thimbles a day. However, some of the machinery is defective, so it can currently only produce…

C. XOR Equation 题目连接: http://www.codeforces.com/contest/635/problem/C Description Two positive integers a and b have a sum of s and a bitwise XOR of x. How many possible values are there for the ordered pair (a, b)? Input The first line of the input…

B. sland Puzzle 题目连接: http://www.codeforces.com/contest/635/problem/B Description A remote island chain contains n islands, labeled 1 through n. Bidirectional bridges connect the islands to form a simple cycle - a bridge connects islands 1 and 2, isl…

A. Orchestra 题目连接: http://www.codeforces.com/contest/635/problem/A Description Paul is at the orchestra. The string section is arranged in an r × c rectangular grid and is filled with violinists with the exception of n violists. Paul really likes vio…

题目链接:http://codeforces.com/contest/755/problem/C 题意:PolandBall 生活在一个森林模型的环境中,定义森林由若干树组成,定义树为K个点,K-1条无向边的图.现在给定每个家庭在对应的树上离他最远的另一个家庭的编号.问这个森林有多少棵树组成. 思路:由于只给出了每个点在树上离他最远的点的坐标而不知道整体结构,但是可以知道该点和给定离他最远的点一定是在同一颗树上,所以维护一个并查集,最后有多少个连通分量就是有多少棵树了. import java.…

题目链接:http://codeforces.com/contest/755/problem/B 题意:给定PolandBall 和EnemyBall 这2个人要说的单词,然后每一回合轮到的人要说一个单词,之前说过的单词不能再说,当轮到某个人的回合没单词说即输.每人都采取最优策略,PolandBall 先说问PolandBall 是否能赢. 思路: 首先两个的单词可以分为相同和不相同两个部分,由于说过的词不能重复说所以比起说不相同的那部分的单词还是说相同的那部分比较优,因为说了一个对面有的但是目…

题目链接:http://codeforces.com/contest/755/problem/A 题意:给定一个正整数N,问你是否存在一个数M使得N*M+1不是素数(M的范围在[1,1000]). 思路:考虑到M的范围很小,直接暴力搞. import java.io.PrintWriter; import java.util.*; public class Main { public static final int MAXN=100000+10; public static boolean i…

A. Orchestra time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Paul is at the orchestra. The string section is arranged in an r × c rectangular grid and is filled with violinists with the ex…

贪心.当前位置满油可达的gas station中,如果有比它小的,则加油至第一个比他小的.没有,则加满油,先到达这些station中最小的.注意数的范围即可. #include <iostream> #include <cstdio> #include <cstring> #include <algorithm> #define LL long long using namespace std; const int MAXN = 200050; int d,…

A. Petr and a calendar time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Petr wants to make a calendar for current month. For this purpose he draws a table in which columns correspond to wee…

http://codeforces.com/contest/760/problem/E 题目大意:现在对栈有m个操作,但是顺序是乱的,现在每输入一个操作要求你输出当前的栈顶, 注意,已有操作要按它们的时间顺序进行. 思路:线段树好题啊啊,我们把push当成+1, pop当成-1,按操作的位置建立线段树,那么如何 寻找栈顶呢,我们计算每个点的后缀,栈顶就是下标最大的>0的后缀,我们拿后缀建立线段树, 剩下的就是区间加减法,和求区间最大值啦. #include<bits/stdc++.h>…