题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2586 题意:给出一棵树还有两个点然后求这两个点的最短距离. 题解:val[a]+val[b]-2*val[root]就是这两个点到根节点的距离再减去它们最近的公共父节点到根节点的距离的两倍 然后就是利用lca来求最近公共父节点.由于是模版题代码上写了一点注释方便理解. #include <iostream> #include <cstring> #include <cstdio&…

Distance Queries   Description Farmer John's cows refused to run in his marathon since he chose a path much too long for their leisurely lifestyle. He therefore wants to find a path of a more reasonable length. The input to this problem consists of t…

Keywords Search Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 57353    Accepted Submission(s): 18820 Problem Description In the modern time, Search engine came into the life of everybody li…

1008. Airline Routes (35) 时间限制 400 ms 内存限制 65536 kB 代码长度限制 8000 B 判题程序 Standard 作者 CHEN, Yue Given a map of airline routes, you are supposed to check if a round trip can be planned between any pair of cities. Input Specification: Each input file cont…

Longest Ordered Subsequence Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 47465   Accepted: 21120 Description A numeric sequence of ai is ordered if a1 < a2 < ... < aN. Let the subsequence of the given numeric sequence (a1, a2, ...…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1712 有n门课,和m天时间.每门课上不同的天数有不同的价值,但是上过这门课后不能再上了,求m天里的最大价值. 分组背包模版题. //#pragma comment(linker, "/STACK:102400000, 102400000") #include <algorithm> #include <iostream> #include <cstdlib&g…

不多说了.就是裸的模版题. 贴代码: <span style="font-family:KaiTi_GB2312;font-size:18px;">#include <queue> #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> #define N 30500 #define M 200000 #define…

用树状数组求逆序数 唯一的坑点就是sum要用long long存 直接贴代码了 以后忘了还能直接看 2333…… PS:和hdu3743代码是一样的,因为两个都是逆序对模版题…… #include<stdio.h> #include<string.h> #include<algorithm> using namespace std; ]; int N; struct num{ int xuhao,num; }nu[]; int qufan(int i){ return…

题意  给出一段初始化全为1的区间  后面可以一段一段更改成 1 或 2 或3 问最后整段区间的和是多少 思路:标准线段树区间和模版题 #include<cstdio> #include<algorithm> #include<set> #include<vector> #include<cstring> #include<iostream> using namespace std; ; struct Node{ int l,r,su…

找新朋友 Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Problem Description 新年快到了,“猪头帮协会”准备搞一个聚会,已经知道现有会员N人,把会员从1到N编号,其中会长的号码是N号,凡是和会长是老朋友的,那么该会员的号码肯定和N有大于1的公约数,否则都是新朋友,现在会长想知道究竟有几个新朋友?请你编程序帮会长计算出来.   Input 第一行是测试数据的组…