LeetCode:Longest Common Prefix

题目链接

Write a function to find the longest common prefix string amongst an array of strings.

题目的意思说的不是很清楚，开始理解成了求任意两个字符串的前缀中的最长者。但是本题的意思是求所有字符串的最长公共前缀，即数组的所有字符串都包含这个前缀。

算法1：逐个字符比较，时间复杂度为O(N*L),N是字符串个数，L是最长前缀的长度

class Solution {
public:string longestCommonPrefix(vector<string> &strs) {int n = strs.size();string res;if(n == 0)return res;for(int pos = 0; pos < strs[0].size(); pos++)//最长前缀的长度不超过strs[0].size()，逐个字符的比较{for(int k = 1; k < n; k++)//strs[0]的第pos个字符分别和strs[1...n-1]的第pos个字符比较{if(strs[k].size() == pos || strs[k][pos] != strs[0][pos])return res;}res.push_back(strs[0][pos]);}return res;}
};

============================

算法2：第0个字符串和其他字符串逐个求前缀 ,所有字符串的最长前缀长度 = min{ prefixLength(strs[0], strs[i]) , 0 < i < n } 本文地址

class Solution {
public:string longestCommonPrefix(vector<string> &strs) {int n = strs.size();if(n == 0)return "";int len = strs[0].size();//最长前缀的长度for(int i = 1; i < n; i++){int k;for(k = 0; k < min(len, (int)strs[i].size()); k++)if(strs[0][k] != strs[i][k])break;if(len > k)len = k;}return strs[0].substr(0, len);}
};

算法2的时间复杂度是O(N*M),N是字符串个数，M = strs[0]和其他字符串的前缀长度的平均值, 算法2中字符的比较次数要比算法1多。例如以下例子

strs[0]: abcdef

strs[1: abcde

strs[2: abcdk

strs[3]ab

按照算法1，只需要比较每个字符串的前3个字符；按照算法2，strs[0]和其他三个字符串分表需要比较6、5、3个字符

转载于:https://www.cnblogs.com/TenosDoIt/p/3856331.html

LeetCode:Longest Common Prefix相关推荐

LeetCode Longest Common Prefix
原题链接在这里:https://leetcode.com/problems/longest-common-prefix/ 题目: Write a function to find the longes ...
LeetCode - Longest Common Prefix
题目: Write a function to find the longest common prefix string amongst an array of strings. 思路: 以第一个字 ...
LeetCode: Longest Common Prefix
string.erase没掌握好,悲了个剧,2次过 1 class Solution { 2 public: 3 string longestCommonPrefix(vector<string ...
[leetcode] Longest Common Prefix 字符窜最长公共前缀判断
题目:略 char* longestCommonPrefix(char** strs, int strsSize) {int i = 0, j = 0;int sum = 0;char *buf = ...
LeetCode 14. Longest Common Prefix字典树 trie树学习之公共前缀字符串
所有字符串的公共前缀最长字符串特点:(1)公共所有字符串前缀 (好像跟没说一样...) (2)在字典树中特点:任意从根节点触发遇见第一个分支为止的字符集合即为目标串参考问题:https://lee ...
LeetCode之Longest Common Prefix
1.题目 Write a function to find the longest common prefix string amongst an array of strings 2.代码实现 pa ...
LeetCode - Easy - 14. Longest Common Prefix
Topic String Description https://leetcode.com/problems/longest-common-prefix/ Write a function to fi ...
LeetCode算法入门- Longest Common Prefix -day13
LeetCode算法入门- Longest Common Prefix -day13 题目描述: Write a function to find the longest common prefix ...
leetcode python3 简单题14. Longest Common Prefix
1.编辑器我使用的是win10+vscode+leetcode+python3 环境配置参见我的博客: 链接 2.第十四题 (1)题目英文: Write a function to find th ...

LeetCode:Longest Common Prefix

LeetCode:Longest Common Prefix相关推荐

最新文章

热门文章