Closest Common Ancestors Time Limit: 10 Seconds      Memory Limit: 32768 KB 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 tr…

Closest Common Ancestors Time Limit: 2000MS   Memory Limit: 10000K Total Submissions: 15446   Accepted: 4944 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…

注意:poj上的数据与zoj不同,第二处输入没有逗号 ' , ' 题意:输出测试用例中是最近公共祖先的节点,以及这个节点作为最近公共祖先的次数. 思路:直接求,两个节点一直往上爬,知道爬到同一个节点,这个节点即为最近公共祖先. 这道题的输入挺······,空格可以随意输入.Note that white-spaces (tabs, spaces and line breaks) can be used freely in the input. 5  :  (  3  ) scanf("%d%1s…

Closest Common Ancestors Time Limit: 2000MS   Memory Limit: 10000K Total Submissions: 13372   Accepted: 4340 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 Ancestors Time Limit: 2000MS   Memory Limit: 10000K Total Submissions: 13370   Accepted: 4338 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…

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…

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…

[简介] LCA(T,u,v):在有根树T中,询问一个距离根最远的结点x,使得x同时为结点u.v的祖先. RMQ(A,i,j):对于线性序列A中,询问区间[i,j]上的最值.见我的博客---RMQ ---- ST(Sparse Table)算法. [LCA算法] 解决LCA问题有多种算法,一种是离线的 Tarjan算法 ,还有在线的倍增法 ,还有就是转换为RMQ问题的在线算法. [LCA转化为RMQ] (一)对有根树T进行DFS,将遍历到的结点按照顺序记下,我们将得到一个长度为2N – 1的序列…

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…

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…