最长公共前缀

 1 class Solution {
 2 public:
 3     string longestCommonPrefix(vector<string>& strs) {
 4 
 5             string s;
 6             char c;
 7             int i = 0, j = 0;
 8             int flag = 0;
 9 
10             s = "";
11             flag = 1;
12             if(strs.size() <= 0)
13                 return s;
14             for (i = 0; i < strs[0].size(); i++) {
15                 c = strs[0][i];
16                 for (j = 1; j < strs.size(); j++) {
17                     if (i < strs[j].size()) {
18                         if (c != strs[j][i])
19                             flag = 0;
20                     }
21                     else
22                         flag = 0;
23                 }
24                 if (!flag)
25                     break;
26                 s += c;
27             }
28 
29             return s;
30     }
31 };