leetcode interview questions: Longest Common Prefix

//需要注意细节
class Solution {
public:
    string longestCommonPrefix(vector<string> &strs) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        //sort(strs.begin(),strs.end());
        string result("");
        if (strs.size()==0) {
            return result;
        }
        
        int idx = 0;
        while(1) {
            for(int i=0;i<strs.size();i++) {
                //特殊情况的考虑
                if(strs[i].length()==0) {
                    return result;
                }
                //string.lengt() 返回值类型为size_t 
                //strs[i].length()-1，当length==0时会出问题
                if(idx>strs[i].length()-1) {
                    return result;
                }
            }
            
            char ch = strs[0][idx];
            for(int i=1;i<strs.size();i++) {
                if (ch != strs[i][idx]) {
                    return result;
                }
            }
            
            result+=ch;
            idx++;
        }
        return result;
    }
};