1. class Solution {
    2.     class Trie{
    3.         struct TrieNode{
    4.             char val;
    5.             TrieNode *children[26] = {0};//这里不初始化会报错
    6.             TrieNode(char val){
    7.                 this->val = val;
    8.             }
    9.         };
    10.     private:
    11.         TrieNode *root;
    12.     public:
    13.         Trie(){
    14.             root = new TrieNode(' ');
    15.         }
    16.             /** Inserts a word into the trie. */
    17.         int insert(string word) {
    18.             TrieNode *cur = root;
    19.             bool isNew = false;
    20.             for(int i = word.length() - 1;i >= 0 ;--i){
    21.                 char c = word[i];
    22.                 if(cur->children[c - 'a'] == nullptr){
    23.                     cur->children[c - 'a'] = new TrieNode(c);
    24.                     isNew = true;
    25.                 }
    26.                 cur = cur->children[c - 'a'];
    27.             }
    28.             if(isNew)return word.length() + 1;
    29.             return 0;
    30.         }
    31.     };
    32. public:
    33.     static bool compare(string s1, string s2){
    34.         return s1.length() > s2.length();
    35.     }
    36.     int minimumLengthEncoding(vector<string>& words) {
    37.         if(words.empty())return 0;
    38.         Trie *trie = new Trie();
    39.         sort(words.begin(), words.end(), compare);
    40.         int len = 0;
    41.         for(string word : words){
    42.             len += trie->insert(word);
    43.         }
    44.         return len;
    45.     }
    46. };