leetcode——14——Longest Common Prefix最长公共前缀

class Solution {
public:
string longestCommonPrefix(vector<string>& strs) {
if(strs.size() == 0)
return "";

string pre = strs[0];
for(int i = 1, j; i < strs.size(); ++ i)
{
for(j = 0; j < pre.size() && j < strs[i].size(); ++ j)
if(pre[j] != strs[i][j])
break;
pre = pre.substr(0, j);
}
return pre;

}
};