Leetcode -- Longest Common Prefix

Solution 02/30/2014:

 
class Solution {  
 public:  
   string longestCommonPrefix(vector<string> &strs) {  
     int n = strs.size();  
     if(!n) {  
       return "";  
     }  
     string& str0 = strs[0];  
     for(int i = 1; i < n ; i++) {  
       string str1 = strs[i];  
       int len = std::min(str0.length(), str1.length());  
       while(str0.substr(0, len) != str1.substr(0, len) && len >= 0) {  
         len--;  
       }  
       if(len) {  
         str0 = str0.substr(0, len);  
       } else {  
         return "";  
       }  
     }  
     return str0;  
   }  
 };