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[LeetCode]Longest Common Prefix

2014-03-11 20:04  庸男勿扰  阅读(124)  评论(0)  编辑  收藏  举报

原题链接：http://oj.leetcode.com/problems/longest-common-prefix/

题目描述：

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

题解：

　　依然是一道分治法解的题，类似的还有http://www.cnblogs.com/codershell/p/3592992.html

 1 class Solution {
 2 public:
 3     string lcp(string str1,string str2){
 4         int len1 = str1.length();
 5         int len2 = str2.length();
 6         int i,j;
 7         for(i=0,j=0; i<len1&&j<len2; i++,j++){
 8             if(str1[i] != str2[j] )
 9                 break;
10         }
11         return str1.substr(0,i);
12     }
13     string longestCommonPrefix(vector<string> &strs) {
14         int size = strs.size();
15         if(size == 0)
16             return "";
17         if(size == 1)
18             return strs[0];
19         vector<string> A,B;
20         for(int i=0; i<size/2; i++){
21             A.push_back(strs[i]);
22         }
23         for(int i=size/2; i<size; i++){
24             B.push_back(strs[i]);
25         }
26         return lcp(longestCommonPrefix(A),longestCommonPrefix(B));
27     }
28 };
View Code