A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the figure, each node is labeled with an integer from {1, 2,...,16}. Node 8 is the root of the tree. Node x is an ancestor of node y if n…

题意:给定一棵树,询问两个节点的最近公共祖先. 输入:第一行T,表示测试组数. 每组测试数据包含一个n,表示节点数目,下面n-1行是连接的边,最后一行是询问 输出:共T行,代表每组的测试结果 /* 倍增LCA 注意这是树,所以边是单向的,深搜的时候从根节点开始搜 */ #include<cstdio> #include<iostream> #include<cstring> #define M 10010 #define S 20 using namespace std…

POJ - 1330 Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000KB   64bit IO Format: %lld & %llu Submit Status Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In t…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 39596   Accepted: 19628 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each…

题目链接:http://poj.org/problem?id=1330 Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 36918   Accepted: 18495 Description A rooted tree is a well-known data structure in computer science and engineering. An example…

POJ 1330 Nearest Common Ancestors / UVALive 2525 Nearest Common Ancestors (最近公共祖先LCA) Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each node is labeled with an…

题目:Nearest Common Ancestors 根据输入建立树,然后求2个结点的最近共同祖先. 注意几点: (1)记录每个结点的父亲,比较层级时要用: (2)记录层级: (3)记录每个结点的孩子,vector<int> v[M]写在主函数里面,放在外面超时. 代码: #include<iostream> #include<vector> #include<cstdio> #include<cstdlib> #include<cstr…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 30147   Accepted: 15413 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the figure, eac…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 14902   Accepted: 7963 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the figure, each…

POJ 1330 Nearest Common Ancestors A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the figure, each node is labeled with an integer from {1, 2,...,16}. Node 8 is the root of the tree. No…

传送门 Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 26612   Accepted: 13734 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:    In the figur…

A - Nearest Common Ancestors Time Limit:1000MS     Memory Limit:10000KB     64bit IO Format:%lld & %llu Submit Status Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figu…

1.输入树中的节点数N,输入树中的N-1条边.最后输入2个点,输出它们的最近公共祖先. 2.裸的最近公共祖先. 3. dfs+ST在线算法: /* LCA(POJ 1330) 在线算法 DFS+ST */ #include<iostream> #include<stdio.h> #include<string.h> using namespace std; ; *MAXN];//rmq数组,就是欧拉序列对应的深度序列 struct ST{ *MAXN]; *MAXN][…

详细讲解见:https://blog.csdn.net/liangzhaoyang1/article/details/52549822 zz:https://www.cnblogs.com/kuangbin/p/3302493.html /* *********************************************** Author :kuangbin Created Time :2013-9-5 0:09:55 File Name :F:\2013ACM练习\专题学习\LCA…

Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each node is labeled with an integer from {1, 2,...,16}. Node 8 is the root of the tree. Node x is an ancestor of…

A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the figure, each node is labeled with an integer from {1, 2,...,16}. Node 8 is the root of the tree. Node x is an ancestor of node y if n…

多校第七场考了一道lca,那么就挑一道水题学习一下吧= = 最简单暴力的方法:建好树后,输入询问的点u,v,先把u全部的祖先标记掉,然后沿着v->rt(根)的顺序检查,第一个被u标记的点即为u,v的公共祖先. 标记的时候又犯老毛病了:while,do while都不对,最后还是while(1)了T^T #include<cstdio> #include<cstring> ; int p[MAXN],vis[MAXN]; int main() { int T,n,u,v; sc…

题目链接:http://poj.org/problem?id=1330 题意:给定一个n个节点的有根树,以及树中的两个节点u,v,求u,v的最近公共祖先. 数据范围:n [2, 10000] 思路:从树根出发进行后序深度优先遍历,设置vis数组实时记录是否已被访问. 每遍历完一棵子树r,把它并入以r的父节点p为代表元的集合.这时判断p是不是所要求的u, v节点之一,如果r==u,且v已访问过,则lca(u, v)必为v所属集合的代表元.p==v的情况类似. 我的第一道LCA问题的Tarjan算法…

题意: 给出一棵树的结构. 给出两个点X和Y,求它俩的LCA. 思路: 只需求两个点的LCA,用了两种方法,一种离线tarjan,一种直接搞. 看代码. 代码: 方法一:直接搞. int const maxn = 10005; int T,n,a,b; int fa[maxn]; int X,Y; int main(){ cin>>T; while(T--){ scanf("%d",&n); mem(fa,-1); rep(i,1,n-1){ scanf("…

LCA思想:http://www.cnblogs.com/hujunzheng/p/3945885.html 在求解最近公共祖先为问题上,用到的是Tarjan的思想,从根结点开始形成一棵深搜树,非常好的处理技巧就是在回溯到结点u的时候,u的子树已经遍历,这时候才把u结点放入合并集合中,这样u结点和所有u的子树中的结点的最近公共祖先就是u了,u和还未遍历的所有u的兄弟结点及子树中的最近公共祖先就是u的父亲结点.以此类推..这样我们在对树深度遍历的时候就很自然的将树中的结点分成若干的集合,两个集合中…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 34657   Accepted: 17585 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the figure, eac…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 18136   Accepted: 9608 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each…

传送门:http://poj.org/problem?id=1330 Nearest Common Ancestors Time Limit: 1000MS Memory Limit: 10000K Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each node is l…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 19728   Accepted: 10460 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:    In the figure, e…

POJ 1470 Closest Common Ancestors(最近公共祖先 LCA) Description Write a program that takes as input a rooted tree and a list of pairs of vertices. For each pair (u,v) the program determines the closest common ancestor of u and v in the tree. The closest co…

POJ.1330 Nearest Common Ancestors (LCA 倍增) 题意分析 给出一棵树,树上有n个点(n-1)条边,n-1个父子的边的关系a-b.接下来给出xy,求出xy的lca节点编号. LCA裸题,用倍增思想. 代码总览 #include <cstdio> #include <algorithm> #include <cstring> #include <cmath> #define nmax 80520 #define demen…

POJ 1330 Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 24209   Accepted: 12604 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below:  In the fi…

任意门:http://poj.org/problem?id=1330 Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 34942   Accepted: 17695 Description A rooted tree is a well-known data structure in computer science and engineering. An example…

POJ 1330 Nearest Common Ancestors 题意:最近公共祖先的裸题 思路:LCA和ST我们已经很熟悉了,但是这里的f[i][j]却有相似却又不同的含义.f[i][j]表示i节点的第2j个父亲是多少   这个代码不是我的,转自 邝斌博客 /* *********************************************** Author :kuangbin Created Time :2013-9-5 9:45:17 File Name :F:\2013AC…

Nearest Common Ancestors Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 37386   Accepted: 18694 Description A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each…