D. Mysterious Present 题目连接: http://www.codeforces.com/contest/4/problem/D Description Peter decided to wish happy birthday to his friend from Australia and send him a card. To make his present more mysterious, he decided to make a chain. Chain here i…

传送门 题意: 现在我们有 n 个信封,然后我们有一张卡片,并且我们知道这张卡片的长和宽. 现给出这 n 个信封的长和宽,我们想形成一个链,这条链的长度就是这条链中所含有的信封的数量: 但是需要满足①信封a可以连接信封b当且仅当信封a的长和宽分别严格小于信封b的长和宽.       ②构成这条长链的所有信封的长和宽分别严格小于卡片的长和宽. 问最多可以形成多长的链,并且输出我们选取的链的编号: 题解: DAG上的动态规划: 如果信封对于任意两个信封 a,b 满足上述条件①②,那么连一条由a指向b…

D. MADMAX time limit per test1 second memory limit per test256 megabytes Problem Description As we all know, Max is the best video game player among her friends. Her friends were so jealous of hers, that they created an actual game just to prove that…

D. Wilbur and Trees Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/596/problem/D Description Wilbur the pig really wants to be a beaver, so he decided today to pretend he is a beaver and bite at trees to cut them down. The…

Codeforces Beta Round #80 (Div. 2 Only) A Blackjack1 题意 一共52张扑克,A代表1或者11,2-10表示自己的数字,其他都表示10 现在你已经有一个queen了,问你有多少种方案,能够得到n点 题解 其实只用考虑三种情况,都考虑一下就好了,实在不行就暴力枚举-- 代码 #include<bits/stdc++.h> using namespace std; int n; int main() { scanf("%d",&…

Codeforces Beta Round #83 (Div. 1 Only) A. Dorm Water Supply 题意 给你一个n点m边的图,保证每个点的入度和出度最多为1 如果这个点入度为0,那么这个点就是水龙头点. 如果这个点的出度为0,那么这个点就是储存点. 现在让你把所有水龙头到储存点的路径都输出出来,且输出这条路径的边权最小值 题解 显然是个仙人掌图,所以直接XJB暴力就好了 代码 #include<bits/stdc++.h> using namespace std; co…

Codeforces Beta Round #79 (Div. 2 Only) http://codeforces.com/contest/102 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 pb push_back #define eb empla…

Codeforces Beta Round #77 (Div. 2 Only) http://codeforces.com/contest/96 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 pb push_back #define eb emplac…

Codeforces Beta Round #76 (Div. 2 Only) http://codeforces.com/contest/94 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 pb push_back #define eb emplac…

Codeforces Beta Round #75 (Div. 2 Only) http://codeforces.com/contest/92 A #include<iostream> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define sqr(x) ((x)*(x)) #define maxn 100005 typedef long long ll; t…