题目地址:POJ 2001 考察的字典树,利用的是建树时将每个点仅仅要走过就累加.最后从根节点開始遍历,当遍历到仅仅有1次走过的时候,就说明这个地方是最短的独立前缀.然后记录下长度,输出就可以. 代码例如以下: #include <iostream> #include <stdio.h> #include <string.h> #include <stdlib.h> #include <math.h> #include <ctype.h&g…

早就听过用字典树求异或最大值,然而没做过.发现一碰到异或的题就GG,而且因为以前做过的一道类似的题(事实上并不类似)限制了思路,蠢啊= =. 题意:一棵带权的树,求任意两点间路径异或的最大值. 题解:设xor(a,b)是求a,b间路径的异或值,那么xor(a,b)=xor(root,a)^xor(root,b).因为如果LCA(a,b)==root时结论显然成立,不然的话就会有重复走过的部分,但是异或有性质x^x=0,所以LCA(a,b)!=root结论依然成立. 这样题目就很简单了.对每一个x…

题目链接:http://poj.org/problem?id=1204 思路分析:由于题目数据较弱,使用暴力搜索:对于所有查找的单词建立一棵字典树,在图中的每个坐标,往8个方向搜索查找即可: 需要注意的是查找时不能匹配了一个单词就不在继续往该方向查找,因为在某个坐标的某个方向上可能会匹配多个单词,所以需要一直 查找直到查找到该方向上最后一个坐标: 代码如下: #include <cstdio> #include <cstring> #include <iostream>…

题目链接:http://poj.org/problem?id=1056 思路: 字典树的简单应用,就是判断当前所有的单词中有木有一个是另一个的前缀,直接套用模板再在Tire定义中加一个bool类型的变量用来判断当前到达的位置是否构成另一个单词的编码 代码: #include<cstdio> #include<cstdlib> #include<iostream> #include<algorithm> #include<cstring> usin…

题目链接:http://poj.org/problem?id=2408 World-renowned Prof. A. N. Agram's current research deals with large anagram groups. He has just found a new application for his theory on the distribution of characters in English language texts. Given such a text…

题目链接: http://poj.org/problem?id=1816 http://bailian.openjudge.cn/practice/1816?lang=en_US Time Limit: 2000MS Memory Limit: 65536K Description A word is a string of lowercases. A word pattern is a string of lowercases, '?'s and '*'s. In a pattern, a '…

Phone List 时间限制:1000 ms  |  内存限制:65535 KB 难度:4   描述 Given a list of phone numbers, determine if it is consistent in the sense that no number is the prefix of another. Let's say the phone catalogue listed these numbers: Emergency 911 Alice 97 625 999…

Babelfish Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 30816   Accepted: 13283 Description You have just moved from Waterloo to a big city. The people here speak an incomprehensible dialect of a foreign language. Fortunately, you have…

Colored Sticks Time Limit: 5000MS   Memory Limit: 128000K Total Submissions: 27134   Accepted: 7186 Description You are given a bunch of wooden sticks. Each endpoint of each stick is colored with some color. Is it possible to align the sticks in a st…

487-3279 Time Limit: 2000MS        Memory Limit: 65536K Total Submissions: 309257        Accepted: 55224 Description Businesses like to have memorable telephone numbers. One way to make a telephone number memorable is to have it spell a memorable wor…