题目链接:http://codeforces.com/problemset/problem/812/B B. Sagheer, the Hausmeister time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Some people leave the lights at their workplaces on when they…

http://codeforces.com/contest/812/problem/B 题意: 有n层楼,每层楼有m个房间,1表示灯开着,0表示灯关了.最两侧的是楼梯. 现在每从一个房间移动到另一个房间需要1时间,走楼梯也需要1时间,求关完所有灯所需的最少时间. 思路: d[i][0]表示第i层楼关完灯后从左边楼梯上楼的最少时间,d[i][1]代表右楼梯. 预处理一下,开两个数组保存每层楼开灯房间的最左边的值和最右边的值,这样也就确定了要走的范围. 对于上面灯全部关了的楼层,可以不用去考虑它.…

预处理每一层最左侧的1的位置,以及最右侧的1的位置. f(i,0)表示第i层,从左侧上来的最小值.f(i,1)表示从右侧上来. 转移方程请看代码. #include<cstdio> #include<algorithm> using namespace std; int n,m,left[20],right[20],f[20][2]; char a[20][110]; int main(){ scanf("%d%d",&n,&m); for(in…

time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output On his trip to Luxor and Aswan, Sagheer went to a Nubian market to buy some souvenirs for his friends and relatives. The market has some str…

http://codeforces.com/contest/812/problem/D 题意: 现在有n个孩子,m个玩具,每次输入x y,表示x孩子想要y玩具,如果y玩具没人玩,那么x就可以去玩,如果y有人玩的话,x就必须等待y玩完后才能玩.如果出现循环,那么这个循环里的孩子都会哭. 现在有q次询问,如果加入x y,会有多少孩子哭. 思路: 建立一棵树,根结点就是第一个玩玩具y的人,它的子树就是等待玩具的人(子树按照等待顺序建树).这样就会形成很多棵树. 这样的话,对于每个询问,我们去找到最后一…

[题意概述] 在一个十字路口 ,给定红绿灯的情况, 按逆时针方向一次给出各个路口的左转,直行,右转,以及行人车道,判断汽车是否有可能撞到行人 [题目分析] 需要在逻辑上清晰,只需要把所有情况列出来即可 [AC] #include<bits/stdc++.h> using namespace std; int main() { ][]; ; i <= ; i++) ; j <= ; j++) scanf("%d",&light[i][j]); int an…

傻逼二分 #include<cstdio> #include<algorithm> using namespace std; typedef long long ll; ll a[100010],b[100010],sum; int n,m; bool check(int x){ for(int i=1;i<=n;++i){ b[i]=a[i]+(ll)i*(ll)x; } sum=0; sort(b+1,b+n+1); for(int i=1;i<=x;++i){ s…

Hard problem 题目链接: http://codeforces.com/contest/706/problem/C Description Vasiliy is fond of solving different tasks. Today he found one he wasn't able to solve himself, so he asks you to help. Vasiliy is given n strings consisting of lowercase Engl…

来自FallDream的博客,未经允许,请勿转载,谢谢. 有毒的一场div2 找了个1300的小号,结果B题题目看错没交  D题题目剧毒 E题差了10秒钟没交上去. 233 ------- A.Sagheer and Crossroads 有一个十字路口,分别给出每个方向左右转和直行以及行人的红绿灯的状态,求有没有可能有行人会被车撞 大判断.  附上大佬@ACMLCZH的代码 #include <cstdio> #include <cstring> ][]; inline int…

A. Sagheer and Crossroads time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Sagheer is walking in the street when he comes to an intersection of two roads. Each road can be represented as two…

A. Sagheer and Crossroads time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Sagheer is walking in the street when he comes to an intersection of two roads. Each road can be represented as two…

题目链接 题面有点长需耐心读题. A.一个人行道上的人被撞有4种情况 1.所在车道有车驶出 2.右边车道有左转车 3.左边车道有右转车 4.对面车道有直行车 #include <bits/stdc++.h> #define rep(i, j, k) for(int i = j;i <= k;i ++) #define rev(i, j, k) for(int i = j;i >= k;i --) using namespace std; typedef long long ll;…

Coloring Trees Problem Description: ZS the Coder and Chris the Baboon has arrived at Udayland! They walked in the park where n trees grow. They decided to be naughty and color the trees in the park. The trees are numbered with integers from 1 to n fr…

题目链接: http://codeforces.com/problemset/problem/268/E E. Playlist time limit per test 1 secondmemory limit per test 256 megabytes 问题描述 Manao's friends often send him new songs. He never listens to them right away. Instead, he compiles them into a play…

题目链接: http://codeforces.com/contest/464/problem/C J. Substitutes in Number time limit per test 1 secondmemory limit per test 256 megabytes 问题描述 Andrew and Eugene are playing a game. Initially, Andrew has string s, consisting of digits. Eugene sends A…

D. Fox And Jumping 题目连接: http://codeforces.com/contest/510/problem/D Description Fox Ciel is playing a game. In this game there is an infinite long tape with cells indexed by integers (positive, negative and zero). At the beginning she is standing at…

B. Maximum Submatrix 2 Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/problemset/problem/375/B Description You are given a matrix consisting of digits zero and one, its size is n × m. You are allowed to rearrange its rows. What is…

题目链接: http://codeforces.com/contest/677/problem/D 题意: 让你求最短的从start->...->1->...->2->...->3->...->...->p的最短路径. 题解: 这题dp的阶段性还是很明显的,相同的值得方格为同一个阶段,然后求从阶段1->2->3...->p的阶段图最短路. 初始化所有a[x][y]==1的格子为起始点到(x,y)坐标的距离. 方程式为dp[x1][y1…

题目链接: http://codeforces.com/contest/378/problem/E 题意: dota选英雄,现在有n个英雄,m个回合,两支队伍: 每一回合两个选择: b 1,队伍一ban掉一个英雄,或是跳过这个回合 p 1,队伍1选一个英雄 现在每个队伍都是最优决策,问最后队伍一的英雄实力和-队伍二的英雄实力和. 题解: 状压dp,决策要倒过来做,也就是dp出后面回合的决策的基础上设计出对自己当前回合对自己最有利的决策.. 注意:只有top m的英雄有可能被选,其他的都不可能被选…

题目链接:http://codeforces.com/problemset/problem/429/B 给你一个矩阵,一个人从(1, 1) ->(n, m),只能向下或者向右: 一个人从(n, 1) ->(1, m),只能向上或者向右.必须有一个相遇点, 相遇点的值不能被取到, 问两个人能得到的最大路径和是多少? dp[i][j]:表示从一个点出发的最大值:先预处理从(1,1) (1,m) (n,1) (n,m)四个点出发的4个dp最大值.然后枚举所有的点,但是这个点不能在边缘,考虑枚举点不够…

B. Strip Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/487/problem/B Description Alexandra has a paper strip with n numbers on it. Let's call them ai from left to right. Now Alexandra wants to split it into some pieces (p…

E. LIS of Sequence Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/486/problem/E Description The next "Data Structures and Algorithms" lesson will be about Longest Increasing Subsequence (LIS for short) of a sequence.…

D. Duff in Beach Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/588/problem/D Description While Duff was resting in the beach, she accidentally found a strange array b0, b1, ..., bl - 1 consisting of l positive integers. Th…

B. Modulo Sum Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/577/problem/B Description 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…

http://codeforces.com/contest/459/problem/E 不明确的是我的代码为啥AC不了,我的是记录we[i]以i为结尾的点的最大权值得边,然后wa在第35  36组数据 然后參考答案了,然后----网上一份题解 大意: 给出一个带权有向图,求经过的边权绝对上升的最长路径(可能是非简单路径,就可以能经过一个点多次)所包括的边数. 题解: 对边按权值排序后,从小到大搞. 设q[x]为已经搞过的边组成的以x点为终点的最长路径包括的边数. 设当前边e[i]为从u到v的边,…

题目:http://codeforces.com/problemset/problem/429/B 第一个人初始位置在(1,1),他必须走到(n,m)只能往下或者往右 第二个人初始位置在(n,1),他必须走到(1,m)只能往上或者往右 每个点都有个权值,要求两个人中间相遇一次且只有一次,相遇的那个点的权值不算,两个人的速度可以不一样,然后求出最大值是多少 思路:他的要求是相遇一次且只有一次,那么画几个图其实就只有两个情况了(这图是借了一位大佬的,[小声bb]) 既然知道了这个图分为了这四个区域,…

题目:https://codeforces.com/problemset/problem/711/C 题意:给你n,m,k,代表n个数的序列,有m种颜色可以涂,0代表未涂颜色,其他代表已经涂好了,连着一段是相同颜色的是一个连通块,求正好有k个连通块的最小花费 思路:首先每个位置有可能有m中颜色,而且要满足k个,我们我们可以推出所有情况 dp[n][m][k] n代表前n个数 m代表当前涂m色 k代表满足k个了 #include<cstdio> #include<cmath> #in…

https://codeforces.com/contest/1111/problem/E 题意 一颗有n个点的树,有q个询问,每次从树挑出k个点,问将这k个点分成m组,需要保证在同一组中不存在一个点是另一个点的祖先这种情况,问有多少中分组方案 题解 首先解决转移问题,假设一次询问全颗树的分组方案数,定义dp[u][i]为到树节点u,分了i组的方案数,其中num(fa[u])为u的祖先节点个数 \(dp[u][i]=dp[fa][i]*(i-num(fa[u]))+dp[fa][i-1]\) 当…

B. Dreamoon and WiFi 题目连接: http://www.codeforces.com/contest/476/problem/B Description Dreamoon is standing at the position 0 on a number line. Drazil is sending a list of commands through Wi-Fi to Dreamoon's smartphone and Dreamoon follows them. Eac…

题目链接: http://codeforces.com/problemset/problem/149/D D. Coloring Brackets time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Once Petya read a problem about a bracket sequence. He gave it much thought but didn't find a solution. Toda…