HDU - 1520 Anniversary party 树形dp
来源:互联网 发布:php小说系统 编辑:程序博客网 时间:2024/06/15 00:31
Anniversary party
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 10129 Accepted Submission(s): 4289
Problem Description
There is going to be a party to celebrate the 80-th Anniversary of the Ural State University. The University has a hierarchical structure of employees. It means that the supervisor relation forms a tree rooted at the rector V. E. Tretyakov. In order to make the party funny for every one, the rector does not want both an employee and his or her immediate supervisor to be present. The personnel office has evaluated conviviality of each employee, so everyone has some number (rating) attached to him or her. Your task is to make a list of guests with the maximal possible sum of guests' conviviality ratings.
Input
Employees are numbered from 1 to N. A first line of input contains a number N. 1 <= N <= 6 000. Each of the subsequent N lines contains the conviviality rating of the corresponding employee. Conviviality rating is an integer number in a range from -128 to 127. After that go T lines that describe a supervisor relation tree. Each line of the tree specification has the form:
L K
It means that the K-th employee is an immediate supervisor of the L-th employee. Input is ended with the line
0 0
L K
It means that the K-th employee is an immediate supervisor of the L-th employee. Input is ended with the line
0 0
Output
Output should contain the maximal sum of guests' ratings.
Sample Input
711111111 32 36 47 44 53 50 0
Sample Output
5
Source
Ural State University Internal Contest October'2000 Students Session
Recommend
linle
第一道树形dp
dp【i】【0】是第i个人不来时的“”rating”最大值
dp【i】【1】是第i个人来时的“rating”最大值
所以dp【i】【0】=∑max(dp【j】【0】,dp【j】【1】) ,其中j是i的直系下属,第一次写的时候忘了注意要取这两个里的最大值,因为i不来时,j可以来也可以不来
dp【i】【1】=∑dp【j】【0】 (j是i的直系下属)
用vector存每个人的直系下属
类似后序遍历这颗树即可
#include<stdio.h>#include<string.h>#include<math.h>#include<string>#include<algorithm>#include<queue>#include<vector>#include<map>#include<set>typedef long long ll;using namespace std;int n;vector <int> w[10000];int l,k,dp[10000][2],book[10000],fa[10000];int tree_dp(int x){int t;book[x]=1;for(int i=0;i<w[x].size();i++){t=w[x].at(i);if(fa[t]==x&&!book[t]){//printf("%d\n",t);tree_dp(t);dp[x][0]+=max(dp[t][1],dp[t][0]);dp[x][1]+=dp[t][0];}}}int main(){int i;while(~scanf("%d",&n)){memset(book,0,sizeof(book));for(i=1;i<=n;i++){scanf("%d",&dp[i][1]);dp[i][0]=0;fa[i]=i;//为了找根节点,开了一个数组存他的直系父节点,应该也有别的简单的求根节点的方法w[i].clear();}while(scanf("%d %d",&l,&k),l,k){w[k].push_back(l);fa[l]=k;}for(i=1;i<=n;i++){if(fa[i]==i){tree_dp(i);printf("%d\n",max(dp[i][0],dp[i][1]));//break;}} } }
0 0
- 树形DP---hdu 1520 Anniversary Party
- HDU 1520 Anniversary party(树形DP入门)
- HDU 1520 Anniversary party-----树形DP
- hdu(1520) Anniversary party(树形dp)
- 【树形DP】 HDU 1520 Anniversary party
- HDU 1520 Anniversary party(简单树形dp)
- HDU 1520 Anniversary party 树形DP
- HDU 1520 Anniversary party (树形DP)
- hdu 1520 Anniversary party(树形dp)
- HDU 1520 Anniversary party(树形DP)
- hdu 1520 Anniversary party(基本树形DP)
- HDU 1520 Anniversary party (树形dp)
- HDU 1520 Anniversary party / 树形DP水题!!!
- hdu 1520 Anniversary party(树形dp)
- hdu 1520Anniversary party(简单树形dp)
- 【树形DP】hdu 1520 Anniversary party
- HDU 1520 - Anniversary party (树形DP)
- poj2342|hdu 1520 Anniversary party 树形dp
- Java中使用FTPClient向FTP服务器上传文件、下载文件
- java与node.js通信
- 数据结构之 排序二叉树总结
- 第四届蓝桥杯A组java--梅森素数
- Facebook数据中心网络架构概览
- HDU - 1520 Anniversary party 树形dp
- 链表初探
- FTC软件系统学习笔记 2.Android Studio入门
- 移动4G网络App页面加载时间过长
- R语言安装sqldb包报错解决办法
- 无限滚动ScrollView两个View重用
- WC2017咸鱼记&THUWC2017垫底记
- Eratosthenes筛选法求小于N的所有素数个数
- leecode 解题总结:39. Combination Sum